Networking
Configuring OpenShift Dedicated networking
Abstract
Chapter 1. About networking
Red Hat OpenShift Networking is an ecosystem of features, plugins, and advanced networking capabilities that enhance Kubernetes networking with advanced networking-related features that your cluster needs to manage network traffic for one or multiple hybrid clusters. This ecosystem of networking capabilities integrates ingress, egress, load balancing, high-performance throughput, security, and inter- and intra-cluster traffic management. The Red Hat OpenShift Networking ecosystem also provides role-based observability tooling to reduce its natural complexities.
The following are some of the most commonly used Red Hat OpenShift Networking features available on your cluster:
- Cluster Network Operator for network plugin management
Primary cluster network provided by either of the following Container Network Interface (CNI) plugins:
- OVN-Kubernetes network plugin, which is the default CNI plugin.
OpenShift SDN network plugin, which was deprecated in OpenShift 4.16 and removed in OpenShift 4.17.
ImportantYou cannot migrate an OpenShift 4.16 cluster that uses the SDN network plugin to OpenShift 4.17 because no migration path currently exists.
Additional resources
Chapter 2. DNS Operator in OpenShift Dedicated
In OpenShift Dedicated, the DNS Operator deploys and manages a CoreDNS instance to provide a name resolution service to pods inside the cluster, enables DNS-based Kubernetes Service discovery, and resolves internal cluster.local
names.
2.1. Checking the status of the DNS Operator
The DNS Operator implements the dns
API from the operator.openshift.io
API group. The Operator deploys CoreDNS using a daemon set, creates a service for the daemon set, and configures the kubelet to instruct pods to use the CoreDNS service IP address for name resolution.
Procedure
The DNS Operator is deployed during installation with a Deployment
object.
Use the
oc get
command to view the deployment status:$ oc get -n openshift-dns-operator deployment/dns-operator
Example output
NAME READY UP-TO-DATE AVAILABLE AGE dns-operator 1/1 1 1 23h
Use the
oc get
command to view the state of the DNS Operator:$ oc get clusteroperator/dns
Example output
NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE MESSAGE dns 4.1.15-0.11 True False False 92m
AVAILABLE
,PROGRESSING
, andDEGRADED
provide information about the status of the Operator.AVAILABLE
isTrue
when at least 1 pod from the CoreDNS daemon set reports anAvailable
status condition, and the DNS service has a cluster IP address.
2.2. View the default DNS
Every new OpenShift Dedicated installation has a dns.operator
named default
.
Procedure
Use the
oc describe
command to view the defaultdns
:$ oc describe dns.operator/default
Example output
Name: default Namespace: Labels: <none> Annotations: <none> API Version: operator.openshift.io/v1 Kind: DNS ... Status: Cluster Domain: cluster.local 1 Cluster IP: 172.30.0.10 2 ...
2.3. Using DNS forwarding
You can use DNS forwarding to override the default forwarding configuration in the /etc/resolv.conf
file in the following ways:
Specify name servers (
spec.servers
) for every zone. If the forwarded zone is the ingress domain managed by OpenShift Dedicated, then the upstream name server must be authorized for the domain.ImportantYou must specify at least one zone. Otherwise, your cluster can lose functionality.
-
Provide a list of upstream DNS servers (
spec.upstreamResolvers
). - Change the default forwarding policy.
A DNS forwarding configuration for the default domain can have both the default servers specified in the /etc/resolv.conf
file and the upstream DNS servers.
Procedure
Modify the DNS Operator object named
default
:$ oc edit dns.operator/default
After you issue the previous command, the Operator creates and updates the config map named
dns-default
with additional server configuration blocks based onspec.servers
.ImportantWhen specifying values for the
zones
parameter, ensure that you only forward to specific zones, such as your intranet. You must specify at least one zone. Otherwise, your cluster can lose functionality.If none of the servers have a zone that matches the query, then name resolution falls back to the upstream DNS servers.
Configuring DNS forwarding
apiVersion: operator.openshift.io/v1 kind: DNS metadata: name: default spec: cache: negativeTTL: 0s positiveTTL: 0s logLevel: Normal nodePlacement: {} operatorLogLevel: Normal servers: - name: example-server 1 zones: - example.com 2 forwardPlugin: policy: Random 3 upstreams: 4 - 1.1.1.1 - 2.2.2.2:5353 upstreamResolvers: 5 policy: Random 6 protocolStrategy: "" 7 transportConfig: {} 8 upstreams: - type: SystemResolvConf 9 - type: Network address: 1.2.3.4 10 port: 53 11 status: clusterDomain: cluster.local clusterIP: x.y.z.10 conditions: ...
- 1
- Must comply with the
rfc6335
service name syntax. - 2
- Must conform to the definition of a subdomain in the
rfc1123
service name syntax. The cluster domain,cluster.local
, is an invalid subdomain for thezones
field. - 3
- Defines the policy to select upstream resolvers listed in the
forwardPlugin
. Default value isRandom
. You can also use the valuesRoundRobin
, andSequential
. - 4
- A maximum of 15
upstreams
is allowed perforwardPlugin
. - 5
- You can use
upstreamResolvers
to override the default forwarding policy and forward DNS resolution to the specified DNS resolvers (upstream resolvers) for the default domain. If you do not provide any upstream resolvers, the DNS name queries go to the servers declared in/etc/resolv.conf
. - 6
- Determines the order in which upstream servers listed in
upstreams
are selected for querying. You can specify one of these values:Random
,RoundRobin
, orSequential
. The default value isSequential
. - 7
- When omitted, the platform chooses a default, normally the protocol of the original client request. Set to
TCP
to specify that the platform should use TCP for all upstream DNS requests, even if the client request uses UDP. - 8
- Used to configure the transport type, server name, and optional custom CA or CA bundle to use when forwarding DNS requests to an upstream resolver.
- 9
- You can specify two types of
upstreams
:SystemResolvConf
orNetwork
.SystemResolvConf
configures the upstream to use/etc/resolv.conf
andNetwork
defines aNetworkresolver
. You can specify one or both. - 10
- If the specified type is
Network
, you must provide an IP address. Theaddress
field must be a valid IPv4 or IPv6 address. - 11
- If the specified type is
Network
, you can optionally provide a port. Theport
field must have a value between1
and65535
. If you do not specify a port for the upstream, the default port is 853.
Additional resources
- For more information on DNS forwarding, see the CoreDNS forward documentation.
2.4. Checking DNS Operator status
You can inspect the status and view the details of the DNS Operator using the oc describe
command.
Procedure
View the status of the DNS Operator:
$ oc describe clusteroperators/dns
Though the messages and spelling might vary in a specific release, the expected status output looks like:
Status: Conditions: Last Transition Time: <date> Message: DNS "default" is available. Reason: AsExpected Status: True Type: Available Last Transition Time: <date> Message: Desired and current number of DNSes are equal Reason: AsExpected Status: False Type: Progressing Last Transition Time: <date> Reason: DNSNotDegraded Status: False Type: Degraded Last Transition Time: <date> Message: DNS default is upgradeable: DNS Operator can be upgraded Reason: DNSUpgradeable Status: True Type: Upgradeable
2.5. Viewing DNS Operator logs
You can view DNS Operator logs by using the oc logs
command.
Procedure
View the logs of the DNS Operator:
$ oc logs -n openshift-dns-operator deployment/dns-operator -c dns-operator
2.6. Setting the CoreDNS log level
Log levels for CoreDNS and the CoreDNS Operator are set by using different methods. You can configure the CoreDNS log level to determine the amount of detail in logged error messages. The valid values for CoreDNS log level are Normal
, Debug
, and Trace
. The default logLevel
is Normal
.
The CoreDNS error log level is always enabled. The following log level settings report different error responses:
-
logLevel
:Normal
enables the "errors" class:log . { class error }
. -
logLevel
:Debug
enables the "denial" class:log . { class denial error }
. -
logLevel
:Trace
enables the "all" class:log . { class all }
.
Procedure
To set
logLevel
toDebug
, enter the following command:$ oc patch dnses.operator.openshift.io/default -p '{"spec":{"logLevel":"Debug"}}' --type=merge
To set
logLevel
toTrace
, enter the following command:$ oc patch dnses.operator.openshift.io/default -p '{"spec":{"logLevel":"Trace"}}' --type=merge
Verification
To ensure the desired log level was set, check the config map:
$ oc get configmap/dns-default -n openshift-dns -o yaml
For example, after setting the
logLevel
toTrace
, you should see this stanza in each server block:errors log . { class all }
2.7. Setting the CoreDNS Operator log level
Log levels for CoreDNS and CoreDNS Operator are set by using different methods. Cluster administrators can configure the Operator log level to more quickly track down OpenShift DNS issues. The valid values for operatorLogLevel
are Normal
, Debug
, and Trace
. Trace
has the most detailed information. The default operatorlogLevel
is Normal
. There are seven logging levels for Operator issues: Trace, Debug, Info, Warning, Error, Fatal, and Panic. After the logging level is set, log entries with that severity or anything above it will be logged.
-
operatorLogLevel: "Normal"
setslogrus.SetLogLevel("Info")
. -
operatorLogLevel: "Debug"
setslogrus.SetLogLevel("Debug")
. -
operatorLogLevel: "Trace"
setslogrus.SetLogLevel("Trace")
.
Procedure
To set
operatorLogLevel
toDebug
, enter the following command:$ oc patch dnses.operator.openshift.io/default -p '{"spec":{"operatorLogLevel":"Debug"}}' --type=merge
To set
operatorLogLevel
toTrace
, enter the following command:$ oc patch dnses.operator.openshift.io/default -p '{"spec":{"operatorLogLevel":"Trace"}}' --type=merge
Verification
To review the resulting change, enter the following command:
$ oc get dnses.operator -A -oyaml
You should see two log level entries. The
operatorLogLevel
applies to OpenShift DNS Operator issues, and thelogLevel
applies to the daemonset of CoreDNS pods:logLevel: Trace operatorLogLevel: Debug
To review the logs for the daemonset, enter the following command:
$ oc logs -n openshift-dns ds/dns-default
2.8. Tuning the CoreDNS cache
For CoreDNS, you can configure the maximum duration of both successful or unsuccessful caching, also known respectively as positive or negative caching. Tuning the cache duration of DNS query responses can reduce the load for any upstream DNS resolvers.
Setting TTL fields to low values could lead to an increased load on the cluster, any upstream resolvers, or both.
Procedure
Edit the DNS Operator object named
default
by running the following command:$ oc edit dns.operator.openshift.io/default
Modify the time-to-live (TTL) caching values:
Configuring DNS caching
apiVersion: operator.openshift.io/v1 kind: DNS metadata: name: default spec: cache: positiveTTL: 1h 1 negativeTTL: 0.5h10m 2
- 1
- The string value
1h
is converted to its respective number of seconds by CoreDNS. If this field is omitted, the value is assumed to be0s
and the cluster uses the internal default value of900s
as a fallback. - 2
- The string value can be a combination of units such as
0.5h10m
and is converted to its respective number of seconds by CoreDNS. If this field is omitted, the value is assumed to be0s
and the cluster uses the internal default value of30s
as a fallback.
Verification
To review the change, look at the config map again by running the following command:
oc get configmap/dns-default -n openshift-dns -o yaml
Verify that you see entries that look like the following example:
cache 3600 { denial 9984 2400 }
Additional resources
For more information on caching, see CoreDNS cache.
2.9. Advanced tasks
2.9.1. Changing the DNS Operator managementState
The DNS Operator manages the CoreDNS component to provide a name resolution service for pods and services in the cluster. The managementState
of the DNS Operator is set to Managed
by default, which means that the DNS Operator is actively managing its resources. You can change it to Unmanaged
, which means the DNS Operator is not managing its resources.
The following are use cases for changing the DNS Operator managementState
:
-
You are a developer and want to test a configuration change to see if it fixes an issue in CoreDNS. You can stop the DNS Operator from overwriting the configuration change by setting the
managementState
toUnmanaged
. -
You are a cluster administrator and have reported an issue with CoreDNS, but need to apply a workaround until the issue is fixed. You can set the
managementState
field of the DNS Operator toUnmanaged
to apply the workaround.
Procedure
Change
managementState
toUnmanaged
in the DNS Operator:oc patch dns.operator.openshift.io default --type merge --patch '{"spec":{"managementState":"Unmanaged"}}'
Review
managementState
of the DNS Operator using thejsonpath
command line JSON parser:$ oc get dns.operator.openshift.io default -ojsonpath='{.spec.managementState}'
Example output
"Unmanaged"
You cannot upgrade while the managementState
is set to Unmanaged
.
2.9.2. Controlling DNS pod placement
The DNS Operator has two daemon sets: one for CoreDNS called dns-default
and one for managing the /etc/hosts
file called node-resolver
.
You might find a need to control which nodes have CoreDNS pods assigned and running, although this is not a common operation. For example, if the cluster administrator has configured security policies that can prohibit communication between pairs of nodes, that would necessitate restricting the set of nodes on which the daemonset for CoreDNS runs. If DNS pods are running on some nodes in the cluster and the nodes where DNS pods are not running have network connectivity to nodes where DNS pods are running, DNS service will be available to all pods.
The node-resolver
daemon set must run on every node host because it adds an entry for the cluster image registry to support pulling images. The node-resolver
pods have only one job: to look up the image-registry.openshift-image-registry.svc
service’s cluster IP address and add it to /etc/hosts
on the node host so that the container runtime can resolve the service name.
As a cluster administrator, you can use a custom node selector to configure the daemon set for CoreDNS to run or not run on certain nodes.
Prerequisites
-
You installed the
oc
CLI. -
You are logged in to the cluster as a user with
cluster-admin
privileges. -
Your DNS Operator
managementState
is set toManaged
.
Procedure
To allow the daemon set for CoreDNS to run on certain nodes, configure a taint and toleration:
Modify the DNS Operator object named
default
:$ oc edit dns.operator/default
Specify a taint key and a toleration for the taint:
spec: nodePlacement: tolerations: - effect: NoExecute key: "dns-only" operators: Equal value: abc tolerationSeconds: 3600 1
- 1
- If the taint is
dns-only
, it can be tolerated indefinitely. You can omittolerationSeconds
.
2.9.3. Configuring DNS forwarding with TLS
When working in a highly regulated environment, you might need the ability to secure DNS traffic when forwarding requests to upstream resolvers so that you can ensure additional DNS traffic and data privacy.
Be aware that CoreDNS caches forwarded connections for 10 seconds. CoreDNS will hold a TCP connection open for those 10 seconds if no request is issued. With large clusters, ensure that your DNS server is aware that it might get many new connections to hold open because you can initiate a connection per node. Set up your DNS hierarchy accordingly to avoid performance issues.
When specifying values for the zones
parameter, ensure that you only forward to specific zones, such as your intranet. You must specify at least one zone. Otherwise, your cluster can lose functionality.
Procedure
Modify the DNS Operator object named
default
:$ oc edit dns.operator/default
Cluster administrators can configure transport layer security (TLS) for forwarded DNS queries.
Configuring DNS forwarding with TLS
apiVersion: operator.openshift.io/v1 kind: DNS metadata: name: default spec: servers: - name: example-server 1 zones: - example.com 2 forwardPlugin: transportConfig: transport: TLS 3 tls: caBundle: name: mycacert serverName: dnstls.example.com 4 policy: Random 5 upstreams: 6 - 1.1.1.1 - 2.2.2.2:5353 upstreamResolvers: 7 transportConfig: transport: TLS tls: caBundle: name: mycacert serverName: dnstls.example.com upstreams: - type: Network 8 address: 1.2.3.4 9 port: 53 10
- 1
- Must comply with the
rfc6335
service name syntax. - 2
- Must conform to the definition of a subdomain in the
rfc1123
service name syntax. The cluster domain,cluster.local
, is an invalid subdomain for thezones
field. The cluster domain,cluster.local
, is an invalidsubdomain
forzones
. - 3
- When configuring TLS for forwarded DNS queries, set the
transport
field to have the valueTLS
. - 4
- When configuring TLS for forwarded DNS queries, this is a mandatory server name used as part of the server name indication (SNI) to validate the upstream TLS server certificate.
- 5
- Defines the policy to select upstream resolvers. Default value is
Random
. You can also use the valuesRoundRobin
, andSequential
. - 6
- Required. Use it to provide upstream resolvers. A maximum of 15
upstreams
entries are allowed perforwardPlugin
entry. - 7
- Optional. You can use it to override the default policy and forward DNS resolution to the specified DNS resolvers (upstream resolvers) for the default domain. If you do not provide any upstream resolvers, the DNS name queries go to the servers in
/etc/resolv.conf
. - 8
- Only the
Network
type is allowed when using TLS and you must provide an IP address.Network
type indicates that this upstream resolver should handle forwarded requests separately from the upstream resolvers listed in/etc/resolv.conf
. - 9
- The
address
field must be a valid IPv4 or IPv6 address. - 10
- You can optionally provide a port. The
port
must have a value between1
and65535
. If you do not specify a port for the upstream, the default port is 853.
NoteIf
servers
is undefined or invalid, the config map only contains the default server.
Verification
View the config map:
$ oc get configmap/dns-default -n openshift-dns -o yaml
Sample DNS ConfigMap based on TLS forwarding example
apiVersion: v1 data: Corefile: | example.com:5353 { forward . 1.1.1.1 2.2.2.2:5353 } bar.com:5353 example.com:5353 { forward . 3.3.3.3 4.4.4.4:5454 1 } .:5353 { errors health kubernetes cluster.local in-addr.arpa ip6.arpa { pods insecure upstream fallthrough in-addr.arpa ip6.arpa } prometheus :9153 forward . /etc/resolv.conf 1.2.3.4:53 { policy Random } cache 30 reload } kind: ConfigMap metadata: labels: dns.operator.openshift.io/owning-dns: default name: dns-default namespace: openshift-dns
- 1
- Changes to the
forwardPlugin
triggers a rolling update of the CoreDNS daemon set.
Additional resources
- For more information on DNS forwarding, see the CoreDNS forward documentation.
Chapter 3. Ingress Operator in OpenShift Dedicated
3.1. OpenShift Dedicated Ingress Operator
When you create your OpenShift Dedicated cluster, pods and services running on the cluster are each allocated their own IP addresses. The IP addresses are accessible to other pods and services running nearby but are not accessible to outside clients. The Ingress Operator implements the IngressController
API and is the component responsible for enabling external access to OpenShift Dedicated cluster services.
The Ingress Operator makes it possible for external clients to access your service by deploying and managing one or more HAProxy-based Ingress Controllers to handle routing. Red Hat Site Reliability Engineers (SRE) manage the Ingress Operator for OpenShift Dedicated clusters. While you cannot alter the settings for the Ingress Operator, you may view the default Ingress Controller configurations, status, and logs as well as the Ingress Operator status.
3.2. The Ingress configuration asset
The installation program generates an asset with an Ingress
resource in the config.openshift.io
API group, cluster-ingress-02-config.yml
.
YAML Definition of the Ingress
resource
apiVersion: config.openshift.io/v1 kind: Ingress metadata: name: cluster spec: domain: apps.openshiftdemos.com
The installation program stores this asset in the cluster-ingress-02-config.yml
file in the manifests/
directory. This Ingress
resource defines the cluster-wide configuration for Ingress. This Ingress configuration is used as follows:
- The Ingress Operator uses the domain from the cluster Ingress configuration as the domain for the default Ingress Controller.
-
The OpenShift API Server Operator uses the domain from the cluster Ingress configuration. This domain is also used when generating a default host for a
Route
resource that does not specify an explicit host.
3.3. Ingress Controller configuration parameters
The IngressController
custom resource (CR) includes optional configuration parameters that you can configure to meet specific needs for your organization.
Parameter | Description |
---|---|
|
The
If empty, the default value is |
|
|
|
For cloud environments, use the
You can configure the following
If not set, the default value is based on
For most platforms, the
If you need to update the
|
|
The
The secret must contain the following keys and data: *
If not set, a wildcard certificate is automatically generated and used. The certificate is valid for the Ingress Controller The in-use certificate, whether generated or user-specified, is automatically integrated with OpenShift Dedicated built-in OAuth server. |
|
|
|
|
|
If not set, the defaults values are used. Note
The nodePlacement: nodeSelector: matchLabels: kubernetes.io/os: linux tolerations: - effect: NoSchedule operator: Exists |
|
If not set, the default value is based on the
When using the
The minimum TLS version for Ingress Controllers is Note
Ciphers and the minimum TLS version of the configured security profile are reflected in the Important
The Ingress Operator converts the TLS |
|
The
The |
|
|
|
|
|
By setting the
By default, the policy is set to
By setting These adjustments are only applied to cleartext, edge-terminated, and re-encrypt routes, and only when using HTTP/1.
For request headers, these adjustments are applied only for routes that have the
|
|
|
|
|
|
For any cookie that you want to capture, the following parameters must be in your
For example: httpCaptureCookies: - matchType: Exact maxLength: 128 name: MYCOOKIE |
|
httpCaptureHeaders: request: - maxLength: 256 name: Connection - maxLength: 128 name: User-Agent response: - maxLength: 256 name: Content-Type - maxLength: 256 name: Content-Length |
|
|
|
The
|
|
The
These connections come from load balancer health probes or web browser speculative connections (preconnect) and can be safely ignored. However, these requests can be caused by network errors, so setting this field to |
3.3.1. Ingress Controller TLS security profiles
TLS security profiles provide a way for servers to regulate which ciphers a connecting client can use when connecting to the server.
3.3.1.1. Understanding TLS security profiles
You can use a TLS (Transport Layer Security) security profile to define which TLS ciphers are required by various OpenShift Dedicated components. The OpenShift Dedicated TLS security profiles are based on Mozilla recommended configurations.
You can specify one of the following TLS security profiles for each component:
Profile | Description |
---|---|
| This profile is intended for use with legacy clients or libraries. The profile is based on the Old backward compatibility recommended configuration.
The Note For the Ingress Controller, the minimum TLS version is converted from 1.0 to 1.1. |
| This profile is the recommended configuration for the majority of clients. It is the default TLS security profile for the Ingress Controller, kubelet, and control plane. The profile is based on the Intermediate compatibility recommended configuration.
The |
| This profile is intended for use with modern clients that have no need for backwards compatibility. This profile is based on the Modern compatibility recommended configuration.
The |
| This profile allows you to define the TLS version and ciphers to use. Warning
Use caution when using a |
When using one of the predefined profile types, the effective profile configuration is subject to change between releases. For example, given a specification to use the Intermediate profile deployed on release X.Y.Z, an upgrade to release X.Y.Z+1 might cause a new profile configuration to be applied, resulting in a rollout.
3.3.1.2. Configuring the TLS security profile for the Ingress Controller
To configure a TLS security profile for an Ingress Controller, edit the IngressController
custom resource (CR) to specify a predefined or custom TLS security profile. If a TLS security profile is not configured, the default value is based on the TLS security profile set for the API server.
Sample IngressController
CR that configures the Old
TLS security profile
apiVersion: operator.openshift.io/v1 kind: IngressController ... spec: tlsSecurityProfile: old: {} type: Old ...
The TLS security profile defines the minimum TLS version and the TLS ciphers for TLS connections for Ingress Controllers.
You can see the ciphers and the minimum TLS version of the configured TLS security profile in the IngressController
custom resource (CR) under Status.Tls Profile
and the configured TLS security profile under Spec.Tls Security Profile
. For the Custom
TLS security profile, the specific ciphers and minimum TLS version are listed under both parameters.
The HAProxy Ingress Controller image supports TLS 1.3
and the Modern
profile.
The Ingress Operator also converts the TLS 1.0
of an Old
or Custom
profile to 1.1
.
Prerequisites
-
You have access to the cluster as a user with the
cluster-admin
role.
Procedure
Edit the
IngressController
CR in theopenshift-ingress-operator
project to configure the TLS security profile:$ oc edit IngressController default -n openshift-ingress-operator
Add the
spec.tlsSecurityProfile
field:Sample
IngressController
CR for aCustom
profileapiVersion: operator.openshift.io/v1 kind: IngressController ... spec: tlsSecurityProfile: type: Custom 1 custom: 2 ciphers: 3 - ECDHE-ECDSA-CHACHA20-POLY1305 - ECDHE-RSA-CHACHA20-POLY1305 - ECDHE-RSA-AES128-GCM-SHA256 - ECDHE-ECDSA-AES128-GCM-SHA256 minTLSVersion: VersionTLS11 ...
- Save the file to apply the changes.
Verification
Verify that the profile is set in the
IngressController
CR:$ oc describe IngressController default -n openshift-ingress-operator
Example output
Name: default Namespace: openshift-ingress-operator Labels: <none> Annotations: <none> API Version: operator.openshift.io/v1 Kind: IngressController ... Spec: ... Tls Security Profile: Custom: Ciphers: ECDHE-ECDSA-CHACHA20-POLY1305 ECDHE-RSA-CHACHA20-POLY1305 ECDHE-RSA-AES128-GCM-SHA256 ECDHE-ECDSA-AES128-GCM-SHA256 Min TLS Version: VersionTLS11 Type: Custom ...
3.3.1.3. Configuring mutual TLS authentication
You can configure the Ingress Controller to enable mutual TLS (mTLS) authentication by setting a spec.clientTLS
value. The clientTLS
value configures the Ingress Controller to verify client certificates. This configuration includes setting a clientCA
value, which is a reference to a config map. The config map contains the PEM-encoded CA certificate bundle that is used to verify a client’s certificate. Optionally, you can also configure a list of certificate subject filters.
If the clientCA
value specifies an X509v3 certificate revocation list (CRL) distribution point, the Ingress Operator downloads and manages a CRL config map based on the HTTP URI X509v3 CRL Distribution Point
specified in each provided certificate. The Ingress Controller uses this config map during mTLS/TLS negotiation. Requests that do not provide valid certificates are rejected.
Prerequisites
-
You have access to the cluster as a user with the
cluster-admin
role. - You have a PEM-encoded CA certificate bundle.
If your CA bundle references a CRL distribution point, you must have also included the end-entity or leaf certificate to the client CA bundle. This certificate must have included an HTTP URI under
CRL Distribution Points
, as described in RFC 5280. For example:Issuer: C=US, O=Example Inc, CN=Example Global G2 TLS RSA SHA256 2020 CA1 Subject: SOME SIGNED CERT X509v3 CRL Distribution Points: Full Name: URI:http://crl.example.com/example.crl
Procedure
In the
openshift-config
namespace, create a config map from your CA bundle:$ oc create configmap \ router-ca-certs-default \ --from-file=ca-bundle.pem=client-ca.crt \1 -n openshift-config
- 1
- The config map data key must be
ca-bundle.pem
, and the data value must be a CA certificate in PEM format.
Edit the
IngressController
resource in theopenshift-ingress-operator
project:$ oc edit IngressController default -n openshift-ingress-operator
Add the
spec.clientTLS
field and subfields to configure mutual TLS:Sample
IngressController
CR for aclientTLS
profile that specifies filtering patternsapiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: clientTLS: clientCertificatePolicy: Required clientCA: name: router-ca-certs-default allowedSubjectPatterns: - "^/CN=example.com/ST=NC/C=US/O=Security/OU=OpenShift$"
-
Optional, get the Distinguished Name (DN) for
allowedSubjectPatterns
by entering the following command.
$ openssl x509 -in custom-cert.pem -noout -subject subject= /CN=example.com/ST=NC/C=US/O=Security/OU=OpenShift
3.4. View the default Ingress Controller
The Ingress Operator is a core feature of OpenShift Dedicated and is enabled out of the box.
Every new OpenShift Dedicated installation has an ingresscontroller
named default. It can be supplemented with additional Ingress Controllers. If the default ingresscontroller
is deleted, the Ingress Operator will automatically recreate it within a minute.
Procedure
View the default Ingress Controller:
$ oc describe --namespace=openshift-ingress-operator ingresscontroller/default
3.5. View Ingress Operator status
You can view and inspect the status of your Ingress Operator.
Procedure
View your Ingress Operator status:
$ oc describe clusteroperators/ingress
3.6. View Ingress Controller logs
You can view your Ingress Controller logs.
Procedure
View your Ingress Controller logs:
$ oc logs --namespace=openshift-ingress-operator deployments/ingress-operator -c <container_name>
3.7. View Ingress Controller status
Your can view the status of a particular Ingress Controller.
Procedure
View the status of an Ingress Controller:
$ oc describe --namespace=openshift-ingress-operator ingresscontroller/<name>
3.8. Creating a custom Ingress Controller
As a cluster administrator, you can create a new custom Ingress Controller. Because the default Ingress Controller might change during OpenShift Dedicated updates, creating a custom Ingress Controller can be helpful when maintaining a configuration manually that persists across cluster updates.
This example provides a minimal spec for a custom Ingress Controller. To further customize your custom Ingress Controller, see "Configuring the Ingress Controller".
Prerequisites
-
Install the OpenShift CLI (
oc
). -
Log in as a user with
cluster-admin
privileges.
Procedure
Create a YAML file that defines the custom
IngressController
object:Example
custom-ingress-controller.yaml
fileapiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: <custom_name> 1 namespace: openshift-ingress-operator spec: defaultCertificate: name: <custom-ingress-custom-certs> 2 replicas: 1 3 domain: <custom_domain> 4
- 1
- Specify the a custom
name
for theIngressController
object. - 2
- Specify the name of the secret with the custom wildcard certificate.
- 3
- Minimum replica needs to be ONE
- 4
- Specify the domain to your domain name. The domain specified on the IngressController object and the domain used for the certificate must match. For example, if the domain value is "custom_domain.mycompany.com", then the certificate must have SAN *.custom_domain.mycompany.com (with the
*.
added to the domain).
Create the object by running the following command:
$ oc create -f custom-ingress-controller.yaml
3.9. Configuring the Ingress Controller
3.9.1. Setting a custom default certificate
As an administrator, you can configure an Ingress Controller to use a custom certificate by creating a Secret resource and editing the IngressController
custom resource (CR).
Prerequisites
- You must have a certificate/key pair in PEM-encoded files, where the certificate is signed by a trusted certificate authority or by a private trusted certificate authority that you configured in a custom PKI.
Your certificate meets the following requirements:
- The certificate is valid for the ingress domain.
-
The certificate uses the
subjectAltName
extension to specify a wildcard domain, such as*.apps.ocp4.example.com
.
You must have an
IngressController
CR. You may use the default one:$ oc --namespace openshift-ingress-operator get ingresscontrollers
Example output
NAME AGE default 10m
If you have intermediate certificates, they must be included in the tls.crt
file of the secret containing a custom default certificate. Order matters when specifying a certificate; list your intermediate certificate(s) after any server certificate(s).
Procedure
The following assumes that the custom certificate and key pair are in the tls.crt
and tls.key
files in the current working directory. Substitute the actual path names for tls.crt
and tls.key
. You also may substitute another name for custom-certs-default
when creating the Secret resource and referencing it in the IngressController CR.
This action will cause the Ingress Controller to be redeployed, using a rolling deployment strategy.
Create a Secret resource containing the custom certificate in the
openshift-ingress
namespace using thetls.crt
andtls.key
files.$ oc --namespace openshift-ingress create secret tls custom-certs-default --cert=tls.crt --key=tls.key
Update the IngressController CR to reference the new certificate secret:
$ oc patch --type=merge --namespace openshift-ingress-operator ingresscontrollers/default \ --patch '{"spec":{"defaultCertificate":{"name":"custom-certs-default"}}}'
Verify the update was effective:
$ echo Q |\ openssl s_client -connect console-openshift-console.apps.<domain>:443 -showcerts 2>/dev/null |\ openssl x509 -noout -subject -issuer -enddate
where:
<domain>
- Specifies the base domain name for your cluster.
Example output
subject=C = US, ST = NC, L = Raleigh, O = RH, OU = OCP4, CN = *.apps.example.com issuer=C = US, ST = NC, L = Raleigh, O = RH, OU = OCP4, CN = example.com notAfter=May 10 08:32:45 2022 GM
TipYou can alternatively apply the following YAML to set a custom default certificate:
apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: defaultCertificate: name: custom-certs-default
The certificate secret name should match the value used to update the CR.
Once the IngressController CR has been modified, the Ingress Operator updates the Ingress Controller’s deployment to use the custom certificate.
3.9.2. Removing a custom default certificate
As an administrator, you can remove a custom certificate that you configured an Ingress Controller to use.
Prerequisites
-
You have access to the cluster as a user with the
cluster-admin
role. -
You have installed the OpenShift CLI (
oc
). - You previously configured a custom default certificate for the Ingress Controller.
Procedure
To remove the custom certificate and restore the certificate that ships with OpenShift Dedicated, enter the following command:
$ oc patch -n openshift-ingress-operator ingresscontrollers/default \ --type json -p $'- op: remove\n path: /spec/defaultCertificate'
There can be a delay while the cluster reconciles the new certificate configuration.
Verification
To confirm that the original cluster certificate is restored, enter the following command:
$ echo Q | \ openssl s_client -connect console-openshift-console.apps.<domain>:443 -showcerts 2>/dev/null | \ openssl x509 -noout -subject -issuer -enddate
where:
<domain>
- Specifies the base domain name for your cluster.
Example output
subject=CN = *.apps.<domain> issuer=CN = ingress-operator@1620633373 notAfter=May 10 10:44:36 2023 GMT
3.9.3. Autoscaling an Ingress Controller
You can automatically scale an Ingress Controller to dynamically meet routing performance or availability requirements, such as the requirement to increase throughput.
The following procedure provides an example for scaling up the default Ingress Controller.
Prerequisites
-
You have the OpenShift CLI (
oc
) installed. -
You have access to an OpenShift Dedicated cluster as a user with the
cluster-admin
role. You installed the Custom Metrics Autoscaler Operator and an associated KEDA Controller.
-
You can install the Operator by using OperatorHub on the web console. After you install the Operator, you can create an instance of
KedaController
.
-
You can install the Operator by using OperatorHub on the web console. After you install the Operator, you can create an instance of
Procedure
Create a service account to authenticate with Thanos by running the following command:
$ oc create -n openshift-ingress-operator serviceaccount thanos && oc describe -n openshift-ingress-operator serviceaccount thanos
Example output
Name: thanos Namespace: openshift-ingress-operator Labels: <none> Annotations: <none> Image pull secrets: thanos-dockercfg-kfvf2 Mountable secrets: thanos-dockercfg-kfvf2 Tokens: <none> Events: <none>
Manually create the service account secret token with the following command:
$ oc apply -f - <<EOF apiVersion: v1 kind: Secret metadata: name: thanos-token namespace: openshift-ingress-operator annotations: kubernetes.io/service-account.name: thanos type: kubernetes.io/service-account-token EOF
Define a
TriggerAuthentication
object within theopenshift-ingress-operator
namespace by using the service account’s token.Create the
TriggerAuthentication
object and pass the value of thesecret
variable to theTOKEN
parameter:$ oc apply -f - <<EOF apiVersion: keda.sh/v1alpha1 kind: TriggerAuthentication metadata: name: keda-trigger-auth-prometheus namespace: openshift-ingress-operator spec: secretTargetRef: - parameter: bearerToken name: thanos-token key: token - parameter: ca name: thanos-token key: ca.crt EOF
Create and apply a role for reading metrics from Thanos:
Create a new role,
thanos-metrics-reader.yaml
, that reads metrics from pods and nodes:thanos-metrics-reader.yaml
apiVersion: rbac.authorization.k8s.io/v1 kind: Role metadata: name: thanos-metrics-reader namespace: openshift-ingress-operator rules: - apiGroups: - "" resources: - pods - nodes verbs: - get - apiGroups: - metrics.k8s.io resources: - pods - nodes verbs: - get - list - watch - apiGroups: - "" resources: - namespaces verbs: - get
Apply the new role by running the following command:
$ oc apply -f thanos-metrics-reader.yaml
Add the new role to the service account by entering the following commands:
$ oc adm policy -n openshift-ingress-operator add-role-to-user thanos-metrics-reader -z thanos --role-namespace=openshift-ingress-operator
$ oc adm policy -n openshift-ingress-operator add-cluster-role-to-user cluster-monitoring-view -z thanos
NoteThe argument
add-cluster-role-to-user
is only required if you use cross-namespace queries. The following step uses a query from thekube-metrics
namespace which requires this argument.Create a new
ScaledObject
YAML file,ingress-autoscaler.yaml
, that targets the default Ingress Controller deployment:Example
ScaledObject
definitionapiVersion: keda.sh/v1alpha1 kind: ScaledObject metadata: name: ingress-scaler namespace: openshift-ingress-operator spec: scaleTargetRef: 1 apiVersion: operator.openshift.io/v1 kind: IngressController name: default envSourceContainerName: ingress-operator minReplicaCount: 1 maxReplicaCount: 20 2 cooldownPeriod: 1 pollingInterval: 1 triggers: - type: prometheus metricType: AverageValue metadata: serverAddress: https://thanos-querier.openshift-monitoring.svc.cluster.local:9091 3 namespace: openshift-ingress-operator 4 metricName: 'kube-node-role' threshold: '1' query: 'sum(kube_node_role{role="worker",service="kube-state-metrics"})' 5 authModes: "bearer" authenticationRef: name: keda-trigger-auth-prometheus
- 1
- The custom resource that you are targeting. In this case, the Ingress Controller.
- 2
- Optional: The maximum number of replicas. If you omit this field, the default maximum is set to 100 replicas.
- 3
- The Thanos service endpoint in the
openshift-monitoring
namespace. - 4
- The Ingress Operator namespace.
- 5
- This expression evaluates to however many worker nodes are present in the deployed cluster.
ImportantIf you are using cross-namespace queries, you must target port 9091 and not port 9092 in the
serverAddress
field. You also must have elevated privileges to read metrics from this port.Apply the custom resource definition by running the following command:
$ oc apply -f ingress-autoscaler.yaml
Verification
Verify that the default Ingress Controller is scaled out to match the value returned by the
kube-state-metrics
query by running the following commands:Use the
grep
command to search the Ingress Controller YAML file for replicas:$ oc get -n openshift-ingress-operator ingresscontroller/default -o yaml | grep replicas:
Example output
replicas: 3
Get the pods in the
openshift-ingress
project:$ oc get pods -n openshift-ingress
Example output
NAME READY STATUS RESTARTS AGE router-default-7b5df44ff-l9pmm 2/2 Running 0 17h router-default-7b5df44ff-s5sl5 2/2 Running 0 3d22h router-default-7b5df44ff-wwsth 2/2 Running 0 66s
3.9.4. Scaling an Ingress Controller
Manually scale an Ingress Controller to meeting routing performance or availability requirements such as the requirement to increase throughput. oc
commands are used to scale the IngressController
resource. The following procedure provides an example for scaling up the default IngressController
.
Scaling is not an immediate action, as it takes time to create the desired number of replicas.
Procedure
View the current number of available replicas for the default
IngressController
:$ oc get -n openshift-ingress-operator ingresscontrollers/default -o jsonpath='{$.status.availableReplicas}'
Example output
2
Scale the default
IngressController
to the desired number of replicas using theoc patch
command. The following example scales the defaultIngressController
to 3 replicas:$ oc patch -n openshift-ingress-operator ingresscontroller/default --patch '{"spec":{"replicas": 3}}' --type=merge
Example output
ingresscontroller.operator.openshift.io/default patched
Verify that the default
IngressController
scaled to the number of replicas that you specified:$ oc get -n openshift-ingress-operator ingresscontrollers/default -o jsonpath='{$.status.availableReplicas}'
Example output
3
TipYou can alternatively apply the following YAML to scale an Ingress Controller to three replicas:
apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: replicas: 3 1
- 1
- If you need a different amount of replicas, change the
replicas
value.
3.9.5. Configuring Ingress access logging
You can configure the Ingress Controller to enable access logs. If you have clusters that do not receive much traffic, then you can log to a sidecar. If you have high traffic clusters, to avoid exceeding the capacity of the logging stack or to integrate with a logging infrastructure outside of OpenShift Dedicated, you can forward logs to a custom syslog endpoint. You can also specify the format for access logs.
Container logging is useful to enable access logs on low-traffic clusters when there is no existing Syslog logging infrastructure, or for short-term use while diagnosing problems with the Ingress Controller.
Syslog is needed for high-traffic clusters where access logs could exceed the OpenShift Logging stack’s capacity, or for environments where any logging solution needs to integrate with an existing Syslog logging infrastructure. The Syslog use-cases can overlap.
Prerequisites
-
Log in as a user with
cluster-admin
privileges.
Procedure
Configure Ingress access logging to a sidecar.
To configure Ingress access logging, you must specify a destination using
spec.logging.access.destination
. To specify logging to a sidecar container, you must specifyContainer
spec.logging.access.destination.type
. The following example is an Ingress Controller definition that logs to aContainer
destination:apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: replicas: 2 logging: access: destination: type: Container
When you configure the Ingress Controller to log to a sidecar, the operator creates a container named
logs
inside the Ingress Controller Pod:$ oc -n openshift-ingress logs deployment.apps/router-default -c logs
Example output
2020-05-11T19:11:50.135710+00:00 router-default-57dfc6cd95-bpmk6 router-default-57dfc6cd95-bpmk6 haproxy[108]: 174.19.21.82:39654 [11/May/2020:19:11:50.133] public be_http:hello-openshift:hello-openshift/pod:hello-openshift:hello-openshift:10.128.2.12:8080 0/0/1/0/1 200 142 - - --NI 1/1/0/0/0 0/0 "GET / HTTP/1.1"
Configure Ingress access logging to a Syslog endpoint.
To configure Ingress access logging, you must specify a destination using
spec.logging.access.destination
. To specify logging to a Syslog endpoint destination, you must specifySyslog
forspec.logging.access.destination.type
. If the destination type isSyslog
, you must also specify a destination endpoint usingspec.logging.access.destination.syslog.address
and you can specify a facility usingspec.logging.access.destination.syslog.facility
. The following example is an Ingress Controller definition that logs to aSyslog
destination:apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: replicas: 2 logging: access: destination: type: Syslog syslog: address: 1.2.3.4 port: 10514
NoteThe
syslog
destination port must be UDP.The
syslog
destination address must be an IP address. It does not support DNS hostname.
Configure Ingress access logging with a specific log format.
You can specify
spec.logging.access.httpLogFormat
to customize the log format. The following example is an Ingress Controller definition that logs to asyslog
endpoint with IP address 1.2.3.4 and port 10514:apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: replicas: 2 logging: access: destination: type: Syslog syslog: address: 1.2.3.4 port: 10514 httpLogFormat: '%ci:%cp [%t] %ft %b/%s %B %bq %HM %HU %HV'
Disable Ingress access logging.
To disable Ingress access logging, leave
spec.logging
orspec.logging.access
empty:apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: replicas: 2 logging: access: null
Allow the Ingress Controller to modify the HAProxy log length when using a sidecar.
Use
spec.logging.access.destination.syslog.maxLength
if you are usingspec.logging.access.destination.type: Syslog
.apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: replicas: 2 logging: access: destination: type: Syslog syslog: address: 1.2.3.4 maxLength: 4096 port: 10514
Use
spec.logging.access.destination.container.maxLength
if you are usingspec.logging.access.destination.type: Container
.apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: replicas: 2 logging: access: destination: type: Container container: maxLength: 8192
3.9.6. Setting Ingress Controller thread count
A cluster administrator can set the thread count to increase the amount of incoming connections a cluster can handle. You can patch an existing Ingress Controller to increase the amount of threads.
Prerequisites
- The following assumes that you already created an Ingress Controller.
Procedure
Update the Ingress Controller to increase the number of threads:
$ oc -n openshift-ingress-operator patch ingresscontroller/default --type=merge -p '{"spec":{"tuningOptions": {"threadCount": 8}}}'
NoteIf you have a node that is capable of running large amounts of resources, you can configure
spec.nodePlacement.nodeSelector
with labels that match the capacity of the intended node, and configurespec.tuningOptions.threadCount
to an appropriately high value.
3.9.7. Configuring an Ingress Controller to use an internal load balancer
When creating an Ingress Controller on cloud platforms, the Ingress Controller is published by a public cloud load balancer by default. As an administrator, you can create an Ingress Controller that uses an internal cloud load balancer.
If you want to change the scope
for an IngressController
, you can change the .spec.endpointPublishingStrategy.loadBalancer.scope
parameter after the custom resource (CR) is created.
Figure 3.1. Diagram of LoadBalancer
The preceding graphic shows the following concepts pertaining to OpenShift Dedicated Ingress LoadBalancerService endpoint publishing strategy:
- You can load balance externally, using the cloud provider load balancer, or internally, using the OpenShift Ingress Controller Load Balancer.
- You can use the single IP address of the load balancer and more familiar ports, such as 8080 and 4200 as shown on the cluster depicted in the graphic.
- Traffic from the external load balancer is directed at the pods, and managed by the load balancer, as depicted in the instance of a down node. See the Kubernetes Services documentation for implementation details.
Prerequisites
-
Install the OpenShift CLI (
oc
). -
Log in as a user with
cluster-admin
privileges.
Procedure
Create an
IngressController
custom resource (CR) in a file named<name>-ingress-controller.yaml
, such as in the following example:apiVersion: operator.openshift.io/v1 kind: IngressController metadata: namespace: openshift-ingress-operator name: <name> 1 spec: domain: <domain> 2 endpointPublishingStrategy: type: LoadBalancerService loadBalancer: scope: Internal 3
Create the Ingress Controller defined in the previous step by running the following command:
$ oc create -f <name>-ingress-controller.yaml 1
- 1
- Replace
<name>
with the name of theIngressController
object.
Optional: Confirm that the Ingress Controller was created by running the following command:
$ oc --all-namespaces=true get ingresscontrollers
3.9.8. Setting the Ingress Controller health check interval
A cluster administrator can set the health check interval to define how long the router waits between two consecutive health checks. This value is applied globally as a default for all routes. The default value is 5 seconds.
Prerequisites
- The following assumes that you already created an Ingress Controller.
Procedure
Update the Ingress Controller to change the interval between back end health checks:
$ oc -n openshift-ingress-operator patch ingresscontroller/default --type=merge -p '{"spec":{"tuningOptions": {"healthCheckInterval": "8s"}}}'
NoteTo override the
healthCheckInterval
for a single route, use the route annotationrouter.openshift.io/haproxy.health.check.interval
3.9.9. Configuring the default Ingress Controller for your cluster to be internal
You can configure the default
Ingress Controller for your cluster to be internal by deleting and recreating it.
If you want to change the scope
for an IngressController
, you can change the .spec.endpointPublishingStrategy.loadBalancer.scope
parameter after the custom resource (CR) is created.
Prerequisites
-
Install the OpenShift CLI (
oc
). -
Log in as a user with
cluster-admin
privileges.
Procedure
Configure the
default
Ingress Controller for your cluster to be internal by deleting and recreating it.$ oc replace --force --wait --filename - <<EOF apiVersion: operator.openshift.io/v1 kind: IngressController metadata: namespace: openshift-ingress-operator name: default spec: endpointPublishingStrategy: type: LoadBalancerService loadBalancer: scope: Internal EOF
3.9.10. Configuring the route admission policy
Administrators and application developers can run applications in multiple namespaces with the same domain name. This is for organizations where multiple teams develop microservices that are exposed on the same hostname.
Allowing claims across namespaces should only be enabled for clusters with trust between namespaces, otherwise a malicious user could take over a hostname. For this reason, the default admission policy disallows hostname claims across namespaces.
Prerequisites
- Cluster administrator privileges.
Procedure
Edit the
.spec.routeAdmission
field of theingresscontroller
resource variable using the following command:$ oc -n openshift-ingress-operator patch ingresscontroller/default --patch '{"spec":{"routeAdmission":{"namespaceOwnership":"InterNamespaceAllowed"}}}' --type=merge
Sample Ingress Controller configuration
spec: routeAdmission: namespaceOwnership: InterNamespaceAllowed ...
TipYou can alternatively apply the following YAML to configure the route admission policy:
apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: routeAdmission: namespaceOwnership: InterNamespaceAllowed
3.9.11. Using wildcard routes
The HAProxy Ingress Controller has support for wildcard routes. The Ingress Operator uses wildcardPolicy
to configure the ROUTER_ALLOW_WILDCARD_ROUTES
environment variable of the Ingress Controller.
The default behavior of the Ingress Controller is to admit routes with a wildcard policy of None
, which is backwards compatible with existing IngressController
resources.
Procedure
Configure the wildcard policy.
Use the following command to edit the
IngressController
resource:$ oc edit IngressController
Under
spec
, set thewildcardPolicy
field toWildcardsDisallowed
orWildcardsAllowed
:spec: routeAdmission: wildcardPolicy: WildcardsDisallowed # or WildcardsAllowed
3.9.12. HTTP header configuration
OpenShift Dedicated provides different methods for working with HTTP headers. When setting or deleting headers, you can use specific fields in the Ingress Controller or an individual route to modify request and response headers. You can also set certain headers by using route annotations. The various ways of configuring headers can present challenges when working together.
You can only set or delete headers within an IngressController
or Route
CR, you cannot append them. If an HTTP header is set with a value, that value must be complete and not require appending in the future. In situations where it makes sense to append a header, such as the X-Forwarded-For header, use the spec.httpHeaders.forwardedHeaderPolicy
field, instead of spec.httpHeaders.actions
.
3.9.12.1. Order of precedence
When the same HTTP header is modified both in the Ingress Controller and in a route, HAProxy prioritizes the actions in certain ways depending on whether it is a request or response header.
- For HTTP response headers, actions specified in the Ingress Controller are executed after the actions specified in a route. This means that the actions specified in the Ingress Controller take precedence.
- For HTTP request headers, actions specified in a route are executed after the actions specified in the Ingress Controller. This means that the actions specified in the route take precedence.
For example, a cluster administrator sets the X-Frame-Options response header with the value DENY
in the Ingress Controller using the following configuration:
Example IngressController
spec
apiVersion: operator.openshift.io/v1 kind: IngressController # ... spec: httpHeaders: actions: response: - name: X-Frame-Options action: type: Set set: value: DENY
A route owner sets the same response header that the cluster administrator set in the Ingress Controller, but with the value SAMEORIGIN
using the following configuration:
Example Route
spec
apiVersion: route.openshift.io/v1 kind: Route # ... spec: httpHeaders: actions: response: - name: X-Frame-Options action: type: Set set: value: SAMEORIGIN
When both the IngressController
spec and Route
spec are configuring the X-Frame-Options response header, then the value set for this header at the global level in the Ingress Controller takes precedence, even if a specific route allows frames. For a request header, the Route
spec value overrides the IngressController
spec value.
This prioritization occurs because the haproxy.config
file uses the following logic, where the Ingress Controller is considered the front end and individual routes are considered the back end. The header value DENY
applied to the front end configurations overrides the same header with the value SAMEORIGIN
that is set in the back end:
frontend public http-response set-header X-Frame-Options 'DENY' frontend fe_sni http-response set-header X-Frame-Options 'DENY' frontend fe_no_sni http-response set-header X-Frame-Options 'DENY' backend be_secure:openshift-monitoring:alertmanager-main http-response set-header X-Frame-Options 'SAMEORIGIN'
Additionally, any actions defined in either the Ingress Controller or a route override values set using route annotations.
3.9.12.2. Special case headers
The following headers are either prevented entirely from being set or deleted, or allowed under specific circumstances:
Header name | Configurable using IngressController spec | Configurable using Route spec | Reason for disallowment | Configurable using another method |
---|---|---|---|---|
| No | No |
The | No |
| No | Yes |
When the | No |
| No | No |
The |
Yes: the |
| No | No | The cookies that HAProxy sets are used for session tracking to map client connections to particular back-end servers. Allowing these headers to be set could interfere with HAProxy’s session affinity and restrict HAProxy’s ownership of a cookie. | Yes:
|
3.9.13. Setting or deleting HTTP request and response headers in an Ingress Controller
You can set or delete certain HTTP request and response headers for compliance purposes or other reasons. You can set or delete these headers either for all routes served by an Ingress Controller or for specific routes.
For example, you might want to migrate an application running on your cluster to use mutual TLS, which requires that your application checks for an X-Forwarded-Client-Cert request header, but the OpenShift Dedicated default Ingress Controller provides an X-SSL-Client-Der request header.
The following procedure modifies the Ingress Controller to set the X-Forwarded-Client-Cert request header, and delete the X-SSL-Client-Der request header.
Prerequisites
-
You have installed the OpenShift CLI (
oc
). -
You have access to an OpenShift Dedicated cluster as a user with the
cluster-admin
role.
Procedure
Edit the Ingress Controller resource:
$ oc -n openshift-ingress-operator edit ingresscontroller/default
Replace the X-SSL-Client-Der HTTP request header with the X-Forwarded-Client-Cert HTTP request header:
apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: httpHeaders: actions: 1 request: 2 - name: X-Forwarded-Client-Cert 3 action: type: Set 4 set: value: "%{+Q}[ssl_c_der,base64]" 5 - name: X-SSL-Client-Der action: type: Delete
- 1
- The list of actions you want to perform on the HTTP headers.
- 2
- The type of header you want to change. In this case, a request header.
- 3
- The name of the header you want to change. For a list of available headers you can set or delete, see HTTP header configuration.
- 4
- The type of action being taken on the header. This field can have the value
Set
orDelete
. - 5
- When setting HTTP headers, you must provide a
value
. The value can be a string from a list of available directives for that header, for exampleDENY
, or it can be a dynamic value that will be interpreted using HAProxy’s dynamic value syntax. In this case, a dynamic value is added.
NoteFor setting dynamic header values for HTTP responses, allowed sample fetchers are
res.hdr
andssl_c_der
. For setting dynamic header values for HTTP requests, allowed sample fetchers arereq.hdr
andssl_c_der
. Both request and response dynamic values can use thelower
andbase64
converters.- Save the file to apply the changes.
3.9.14. Using X-Forwarded headers
You configure the HAProxy Ingress Controller to specify a policy for how to handle HTTP headers including Forwarded
and X-Forwarded-For
. The Ingress Operator uses the HTTPHeaders
field to configure the ROUTER_SET_FORWARDED_HEADERS
environment variable of the Ingress Controller.
Procedure
Configure the
HTTPHeaders
field for the Ingress Controller.Use the following command to edit the
IngressController
resource:$ oc edit IngressController
Under
spec
, set theHTTPHeaders
policy field toAppend
,Replace
,IfNone
, orNever
:apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: httpHeaders: forwardedHeaderPolicy: Append
Example use cases
As a cluster administrator, you can:
Configure an external proxy that injects the
X-Forwarded-For
header into each request before forwarding it to an Ingress Controller.To configure the Ingress Controller to pass the header through unmodified, you specify the
never
policy. The Ingress Controller then never sets the headers, and applications receive only the headers that the external proxy provides.Configure the Ingress Controller to pass the
X-Forwarded-For
header that your external proxy sets on external cluster requests through unmodified.To configure the Ingress Controller to set the
X-Forwarded-For
header on internal cluster requests, which do not go through the external proxy, specify theif-none
policy. If an HTTP request already has the header set through the external proxy, then the Ingress Controller preserves it. If the header is absent because the request did not come through the proxy, then the Ingress Controller adds the header.
As an application developer, you can:
Configure an application-specific external proxy that injects the
X-Forwarded-For
header.To configure an Ingress Controller to pass the header through unmodified for an application’s Route, without affecting the policy for other Routes, add an annotation
haproxy.router.openshift.io/set-forwarded-headers: if-none
orhaproxy.router.openshift.io/set-forwarded-headers: never
on the Route for the application.NoteYou can set the
haproxy.router.openshift.io/set-forwarded-headers
annotation on a per route basis, independent from the globally set value for the Ingress Controller.
3.9.15. Enabling HTTP/2 Ingress connectivity
You can enable transparent end-to-end HTTP/2 connectivity in HAProxy. It allows application owners to make use of HTTP/2 protocol capabilities, including single connection, header compression, binary streams, and more.
You can enable HTTP/2 connectivity for an individual Ingress Controller or for the entire cluster.
To enable the use of HTTP/2 for the connection from the client to HAProxy, a route must specify a custom certificate. A route that uses the default certificate cannot use HTTP/2. This restriction is necessary to avoid problems from connection coalescing, where the client re-uses a connection for different routes that use the same certificate.
The connection from HAProxy to the application pod can use HTTP/2 only for re-encrypt routes and not for edge-terminated or insecure routes. This restriction is because HAProxy uses Application-Level Protocol Negotiation (ALPN), which is a TLS extension, to negotiate the use of HTTP/2 with the back-end. The implication is that end-to-end HTTP/2 is possible with passthrough and re-encrypt and not with insecure or edge-terminated routes.
For non-passthrough routes, the Ingress Controller negotiates its connection to the application independently of the connection from the client. This means a client may connect to the Ingress Controller and negotiate HTTP/1.1, and the Ingress Controller may then connect to the application, negotiate HTTP/2, and forward the request from the client HTTP/1.1 connection using the HTTP/2 connection to the application. This poses a problem if the client subsequently tries to upgrade its connection from HTTP/1.1 to the WebSocket protocol, because the Ingress Controller cannot forward WebSocket to HTTP/2 and cannot upgrade its HTTP/2 connection to WebSocket. Consequently, if you have an application that is intended to accept WebSocket connections, it must not allow negotiating the HTTP/2 protocol or else clients will fail to upgrade to the WebSocket protocol.
Procedure
Enable HTTP/2 on a single Ingress Controller.
To enable HTTP/2 on an Ingress Controller, enter the
oc annotate
command:$ oc -n openshift-ingress-operator annotate ingresscontrollers/<ingresscontroller_name> ingress.operator.openshift.io/default-enable-http2=true
Replace
<ingresscontroller_name>
with the name of the Ingress Controller to annotate.
Enable HTTP/2 on the entire cluster.
To enable HTTP/2 for the entire cluster, enter the
oc annotate
command:$ oc annotate ingresses.config/cluster ingress.operator.openshift.io/default-enable-http2=true
TipYou can alternatively apply the following YAML to add the annotation:
apiVersion: config.openshift.io/v1 kind: Ingress metadata: name: cluster annotations: ingress.operator.openshift.io/default-enable-http2: "true"
3.9.16. Configuring the PROXY protocol for an Ingress Controller
A cluster administrator can configure the PROXY protocol when an Ingress Controller uses either the HostNetwork
, NodePortService
, or Private
endpoint publishing strategy types. The PROXY protocol enables the load balancer to preserve the original client addresses for connections that the Ingress Controller receives. The original client addresses are useful for logging, filtering, and injecting HTTP headers. In the default configuration, the connections that the Ingress Controller receives only contain the source address that is associated with the load balancer.
The default Ingress Controller with installer-provisioned clusters on non-cloud platforms that use a Keepalived Ingress Virtual IP (VIP) do not support the PROXY protocol.
The PROXY protocol enables the load balancer to preserve the original client addresses for connections that the Ingress Controller receives. The original client addresses are useful for logging, filtering, and injecting HTTP headers. In the default configuration, the connections that the Ingress Controller receives contain only the source IP address that is associated with the load balancer.
For a passthrough route configuration, servers in OpenShift Dedicated clusters cannot observe the original client source IP address. If you need to know the original client source IP address, configure Ingress access logging for your Ingress Controller so that you can view the client source IP addresses.
For re-encrypt and edge routes, the OpenShift Dedicated router sets the Forwarded
and X-Forwarded-For
headers so that application workloads check the client source IP address.
For more information about Ingress access logging, see "Configuring Ingress access logging".
Configuring the PROXY protocol for an Ingress Controller is not supported when using the LoadBalancerService
endpoint publishing strategy type. This restriction is because when OpenShift Dedicated runs in a cloud platform, and an Ingress Controller specifies that a service load balancer should be used, the Ingress Operator configures the load balancer service and enables the PROXY protocol based on the platform requirement for preserving source addresses.
You must configure both OpenShift Dedicated and the external load balancer to use either the PROXY protocol or TCP.
This feature is not supported in cloud deployments. This restriction is because when OpenShift Dedicated runs in a cloud platform, and an Ingress Controller specifies that a service load balancer should be used, the Ingress Operator configures the load balancer service and enables the PROXY protocol based on the platform requirement for preserving source addresses.
You must configure both OpenShift Dedicated and the external load balancer to either use the PROXY protocol or to use Transmission Control Protocol (TCP).
Prerequisites
- You created an Ingress Controller.
Procedure
Edit the Ingress Controller resource by entering the following command in your CLI:
$ oc -n openshift-ingress-operator edit ingresscontroller/default
Set the PROXY configuration:
If your Ingress Controller uses the
HostNetwork
endpoint publishing strategy type, set thespec.endpointPublishingStrategy.hostNetwork.protocol
subfield toPROXY
:Sample
hostNetwork
configuration toPROXY
# ... spec: endpointPublishingStrategy: hostNetwork: protocol: PROXY type: HostNetwork # ...
If your Ingress Controller uses the
NodePortService
endpoint publishing strategy type, set thespec.endpointPublishingStrategy.nodePort.protocol
subfield toPROXY
:Sample
nodePort
configuration toPROXY
# ... spec: endpointPublishingStrategy: nodePort: protocol: PROXY type: NodePortService # ...
If your Ingress Controller uses the
Private
endpoint publishing strategy type, set thespec.endpointPublishingStrategy.private.protocol
subfield toPROXY
:Sample
private
configuration toPROXY
# ... spec: endpointPublishingStrategy: private: protocol: PROXY type: Private # ...
Additional resources
3.9.17. Specifying an alternative cluster domain using the appsDomain option
As a cluster administrator, you can specify an alternative to the default cluster domain for user-created routes by configuring the appsDomain
field. The appsDomain
field is an optional domain for OpenShift Dedicated to use instead of the default, which is specified in the domain
field. If you specify an alternative domain, it overrides the default cluster domain for the purpose of determining the default host for a new route.
For example, you can use the DNS domain for your company as the default domain for routes and ingresses for applications running on your cluster.
Prerequisites
- You deployed an OpenShift Dedicated cluster.
-
You installed the
oc
command line interface.
Procedure
Configure the
appsDomain
field by specifying an alternative default domain for user-created routes.Edit the ingress
cluster
resource:$ oc edit ingresses.config/cluster -o yaml
Edit the YAML file:
Sample
appsDomain
configuration totest.example.com
apiVersion: config.openshift.io/v1 kind: Ingress metadata: name: cluster spec: domain: apps.example.com 1 appsDomain: <test.example.com> 2
Verify that an existing route contains the domain name specified in the
appsDomain
field by exposing the route and verifying the route domain change:NoteWait for the
openshift-apiserver
finish rolling updates before exposing the route.Expose the route:
$ oc expose service hello-openshift route.route.openshift.io/hello-openshift exposed
Example output
$ oc get routes NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD hello-openshift hello_openshift-<my_project>.test.example.com hello-openshift 8080-tcp None
3.9.18. Converting HTTP header case
HAProxy lowercases HTTP header names by default; for example, changing Host: xyz.com
to host: xyz.com
. If legacy applications are sensitive to the capitalization of HTTP header names, use the Ingress Controller spec.httpHeaders.headerNameCaseAdjustments
API field for a solution to accommodate legacy applications until they can be fixed.
OpenShift Dedicated includes HAProxy 2.8. If you want to update to this version of the web-based load balancer, ensure that you add the spec.httpHeaders.headerNameCaseAdjustments
section to your cluster’s configuration file.
As a cluster administrator, you can convert the HTTP header case by entering the oc patch
command or by setting the HeaderNameCaseAdjustments
field in the Ingress Controller YAML file.
Prerequisites
-
You have installed the OpenShift CLI (
oc
). -
You have access to the cluster as a user with the
cluster-admin
role.
Procedure
Capitalize an HTTP header by using the
oc patch
command.Change the HTTP header from
host
toHost
by running the following command:$ oc -n openshift-ingress-operator patch ingresscontrollers/default --type=merge --patch='{"spec":{"httpHeaders":{"headerNameCaseAdjustments":["Host"]}}}'
Create a
Route
resource YAML file so that the annotation can be applied to the application.Example of a route named
my-application
apiVersion: route.openshift.io/v1 kind: Route metadata: annotations: haproxy.router.openshift.io/h1-adjust-case: true 1 name: <application_name> namespace: <application_name> # ...
- 1
- Set
haproxy.router.openshift.io/h1-adjust-case
so that the Ingress Controller can adjust thehost
request header as specified.
Specify adjustments by configuring the
HeaderNameCaseAdjustments
field in the Ingress Controller YAML configuration file.The following example Ingress Controller YAML file adjusts the
host
header toHost
for HTTP/1 requests to appropriately annotated routes:Example Ingress Controller YAML
apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: httpHeaders: headerNameCaseAdjustments: - Host
The following example route enables HTTP response header name case adjustments by using the
haproxy.router.openshift.io/h1-adjust-case
annotation:Example route YAML
apiVersion: route.openshift.io/v1 kind: Route metadata: annotations: haproxy.router.openshift.io/h1-adjust-case: true 1 name: my-application namespace: my-application spec: to: kind: Service name: my-application
- 1
- Set
haproxy.router.openshift.io/h1-adjust-case
to true.
3.9.19. Using router compression
You configure the HAProxy Ingress Controller to specify router compression globally for specific MIME types. You can use the mimeTypes
variable to define the formats of MIME types to which compression is applied. The types are: application, image, message, multipart, text, video, or a custom type prefaced by "X-". To see the full notation for MIME types and subtypes, see RFC1341.
Memory allocated for compression can affect the max connections. Additionally, compression of large buffers can cause latency, like heavy regex or long lists of regex.
Not all MIME types benefit from compression, but HAProxy still uses resources to try to compress if instructed to. Generally, text formats, such as html, css, and js, formats benefit from compression, but formats that are already compressed, such as image, audio, and video, benefit little in exchange for the time and resources spent on compression.
Procedure
Configure the
httpCompression
field for the Ingress Controller.Use the following command to edit the
IngressController
resource:$ oc edit -n openshift-ingress-operator ingresscontrollers/default
Under
spec
, set thehttpCompression
policy field tomimeTypes
and specify a list of MIME types that should have compression applied:apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: default namespace: openshift-ingress-operator spec: httpCompression: mimeTypes: - "text/html" - "text/css; charset=utf-8" - "application/json" ...
3.9.20. Exposing router metrics
You can expose the HAProxy router metrics by default in Prometheus format on the default stats port, 1936. The external metrics collection and aggregation systems such as Prometheus can access the HAProxy router metrics. You can view the HAProxy router metrics in a browser in the HTML and comma separated values (CSV) format.
Prerequisites
- You configured your firewall to access the default stats port, 1936.
Procedure
Get the router pod name by running the following command:
$ oc get pods -n openshift-ingress
Example output
NAME READY STATUS RESTARTS AGE router-default-76bfffb66c-46qwp 1/1 Running 0 11h
Get the router’s username and password, which the router pod stores in the
/var/lib/haproxy/conf/metrics-auth/statsUsername
and/var/lib/haproxy/conf/metrics-auth/statsPassword
files:Get the username by running the following command:
$ oc rsh <router_pod_name> cat metrics-auth/statsUsername
Get the password by running the following command:
$ oc rsh <router_pod_name> cat metrics-auth/statsPassword
Get the router IP and metrics certificates by running the following command:
$ oc describe pod <router_pod>
Get the raw statistics in Prometheus format by running the following command:
$ curl -u <user>:<password> http://<router_IP>:<stats_port>/metrics
Access the metrics securely by running the following command:
$ curl -u user:password https://<router_IP>:<stats_port>/metrics -k
Access the default stats port, 1936, by running the following command:
$ curl -u <user>:<password> http://<router_IP>:<stats_port>/metrics
Example 3.1. Example output
... # HELP haproxy_backend_connections_total Total number of connections. # TYPE haproxy_backend_connections_total gauge haproxy_backend_connections_total{backend="http",namespace="default",route="hello-route"} 0 haproxy_backend_connections_total{backend="http",namespace="default",route="hello-route-alt"} 0 haproxy_backend_connections_total{backend="http",namespace="default",route="hello-route01"} 0 ... # HELP haproxy_exporter_server_threshold Number of servers tracked and the current threshold value. # TYPE haproxy_exporter_server_threshold gauge haproxy_exporter_server_threshold{type="current"} 11 haproxy_exporter_server_threshold{type="limit"} 500 ... # HELP haproxy_frontend_bytes_in_total Current total of incoming bytes. # TYPE haproxy_frontend_bytes_in_total gauge haproxy_frontend_bytes_in_total{frontend="fe_no_sni"} 0 haproxy_frontend_bytes_in_total{frontend="fe_sni"} 0 haproxy_frontend_bytes_in_total{frontend="public"} 119070 ... # HELP haproxy_server_bytes_in_total Current total of incoming bytes. # TYPE haproxy_server_bytes_in_total gauge haproxy_server_bytes_in_total{namespace="",pod="",route="",server="fe_no_sni",service=""} 0 haproxy_server_bytes_in_total{namespace="",pod="",route="",server="fe_sni",service=""} 0 haproxy_server_bytes_in_total{namespace="default",pod="docker-registry-5-nk5fz",route="docker-registry",server="10.130.0.89:5000",service="docker-registry"} 0 haproxy_server_bytes_in_total{namespace="default",pod="hello-rc-vkjqx",route="hello-route",server="10.130.0.90:8080",service="hello-svc-1"} 0 ...
Launch the stats window by entering the following URL in a browser:
http://<user>:<password>@<router_IP>:<stats_port>
Optional: Get the stats in CSV format by entering the following URL in a browser:
http://<user>:<password>@<router_ip>:1936/metrics;csv
3.9.21. Customizing HAProxy error code response pages
As a cluster administrator, you can specify a custom error code response page for either 503, 404, or both error pages. The HAProxy router serves a 503 error page when the application pod is not running or a 404 error page when the requested URL does not exist. For example, if you customize the 503 error code response page, then the page is served when the application pod is not running, and the default 404 error code HTTP response page is served by the HAProxy router for an incorrect route or a non-existing route.
Custom error code response pages are specified in a config map then patched to the Ingress Controller. The config map keys have two available file names as follows: error-page-503.http
and error-page-404.http
.
Custom HTTP error code response pages must follow the HAProxy HTTP error page configuration guidelines. Here is an example of the default OpenShift Dedicated HAProxy router http 503 error code response page. You can use the default content as a template for creating your own custom page.
By default, the HAProxy router serves only a 503 error page when the application is not running or when the route is incorrect or non-existent. This default behavior is the same as the behavior on OpenShift Dedicated 4.8 and earlier. If a config map for the customization of an HTTP error code response is not provided, and you are using a custom HTTP error code response page, the router serves a default 404 or 503 error code response page.
If you use the OpenShift Dedicated default 503 error code page as a template for your customizations, the headers in the file require an editor that can use CRLF line endings.
Procedure
Create a config map named
my-custom-error-code-pages
in theopenshift-config
namespace:$ oc -n openshift-config create configmap my-custom-error-code-pages \ --from-file=error-page-503.http \ --from-file=error-page-404.http
ImportantIf you do not specify the correct format for the custom error code response page, a router pod outage occurs. To resolve this outage, you must delete or correct the config map and delete the affected router pods so they can be recreated with the correct information.
Patch the Ingress Controller to reference the
my-custom-error-code-pages
config map by name:$ oc patch -n openshift-ingress-operator ingresscontroller/default --patch '{"spec":{"httpErrorCodePages":{"name":"my-custom-error-code-pages"}}}' --type=merge
The Ingress Operator copies the
my-custom-error-code-pages
config map from theopenshift-config
namespace to theopenshift-ingress
namespace. The Operator names the config map according to the pattern,<your_ingresscontroller_name>-errorpages
, in theopenshift-ingress
namespace.Display the copy:
$ oc get cm default-errorpages -n openshift-ingress
Example output
NAME DATA AGE default-errorpages 2 25s 1
- 1
- The example config map name is
default-errorpages
because thedefault
Ingress Controller custom resource (CR) was patched.
Confirm that the config map containing the custom error response page mounts on the router volume where the config map key is the filename that has the custom HTTP error code response:
For 503 custom HTTP custom error code response:
$ oc -n openshift-ingress rsh <router_pod> cat /var/lib/haproxy/conf/error_code_pages/error-page-503.http
For 404 custom HTTP custom error code response:
$ oc -n openshift-ingress rsh <router_pod> cat /var/lib/haproxy/conf/error_code_pages/error-page-404.http
Verification
Verify your custom error code HTTP response:
Create a test project and application:
$ oc new-project test-ingress
$ oc new-app django-psql-example
For 503 custom http error code response:
- Stop all the pods for the application.
Run the following curl command or visit the route hostname in the browser:
$ curl -vk <route_hostname>
For 404 custom http error code response:
- Visit a non-existent route or an incorrect route.
Run the following curl command or visit the route hostname in the browser:
$ curl -vk <route_hostname>
Check if the
errorfile
attribute is properly in thehaproxy.config
file:$ oc -n openshift-ingress rsh <router> cat /var/lib/haproxy/conf/haproxy.config | grep errorfile
3.9.22. Setting the Ingress Controller maximum connections
A cluster administrator can set the maximum number of simultaneous connections for OpenShift router deployments. You can patch an existing Ingress Controller to increase the maximum number of connections.
Prerequisites
- The following assumes that you already created an Ingress Controller
Procedure
Update the Ingress Controller to change the maximum number of connections for HAProxy:
$ oc -n openshift-ingress-operator patch ingresscontroller/default --type=merge -p '{"spec":{"tuningOptions": {"maxConnections": 7500}}}'
WarningIf you set the
spec.tuningOptions.maxConnections
value greater than the current operating system limit, the HAProxy process will not start. See the table in the "Ingress Controller configuration parameters" section for more information about this parameter.
3.10. OpenShift Dedicated Ingress Operator configurations
The following table details the components of the Ingress Operator and if Red Hat Site Reliability Engineers (SRE) maintains this component on OpenShift Dedicated clusters.
Ingress component | Managed by | Default configuration? |
---|---|---|
Scaling Ingress Controller | SRE | Yes |
Ingress Operator thread count | SRE | Yes |
Ingress Controller access logging | SRE | Yes |
Ingress Controller sharding | SRE | Yes |
Ingress Controller route admission policy | SRE | Yes |
Ingress Controller wildcard routes | SRE | Yes |
Ingress Controller X-Forwarded headers | SRE | Yes |
Ingress Controller route compression | SRE | Yes |
Chapter 4. Network verification for OpenShift Dedicated clusters
Network verification checks run automatically when you deploy an OpenShift Dedicated cluster into an existing Virtual Private Cloud (VPC) or create an additional machine pool with a subnet that is new to your cluster. The checks validate your network configuration and highlight errors, enabling you to resolve configuration issues prior to deployment.
You can also run the network verification checks manually to validate the configuration for an existing cluster.
4.1. Understanding network verification for OpenShift Dedicated clusters
When you deploy an OpenShift Dedicated cluster into an existing Virtual Private Cloud (VPC) or create an additional machine pool with a subnet that is new to your cluster, network verification runs automatically. This helps you identify and resolve configuration issues prior to deployment.
When you prepare to install your cluster by using Red Hat OpenShift Cluster Manager, the automatic checks run after you input a subnet into a subnet ID field on the Virtual Private Cloud (VPC) subnet settings page.
When you add a machine pool with a subnet that is new to your cluster, the automatic network verification checks the subnet to ensure that network connectivity is available before the machine pool is provisioned.
After automatic network verification completes, a record is sent to the service log. The record provides the results of the verification check, including any network configuration errors. You can resolve the identified issues before a deployment and the deployment has a greater chance of success.
You can also run the network verification manually for an existing cluster. This enables you to verify the network configuration for your cluster after making configuration changes. For steps to run the network verification checks manually, see Running the network verification manually.
4.2. Scope of the network verification checks
The network verification includes checks for each of the following requirements:
- The parent Virtual Private Cloud (VPC) exists.
- All specified subnets belong to the VPC.
-
The VPC has
enableDnsSupport
enabled. -
The VPC has
enableDnsHostnames
enabled. - Egress is available to the required domain and port combinations that are specified in the AWS firewall prerequisites section.
4.3. Automatic network verification bypassing
You can bypass the automatic network verification if you want to deploy an OpenShift Dedicated cluster with known network configuration issues into an existing Virtual Private Cloud (VPC).
If you bypass the network verification when you create a cluster, the cluster has a limited support status. After installation, you can resolve the issues and then manually run the network verification. The limited support status is removed after the verification succeeds.
When you install a cluster into an existing VPC by using Red Hat OpenShift Cluster Manager, you can bypass the automatic verification by selecting Bypass network verification on the Virtual Private Cloud (VPC) subnet settings page.
4.4. Running the network verification manually
You can manually run the network verification checks for an existing OpenShift Dedicated cluster by using Red Hat OpenShift Cluster Manager.
Prerequisites
- You have an existing OpenShift Dedicated cluster.
- You are the cluster owner or you have the cluster editor role.
Procedure
- Navigate to OpenShift Cluster Manager and select your cluster.
- Select Verify networking from the Actions drop-down menu.
Chapter 5. Configuring a cluster-wide proxy
If you are using an existing Virtual Private Cloud (VPC), you can configure a cluster-wide proxy during an OpenShift Dedicated cluster installation or after the cluster is installed. When you enable a proxy, the core cluster components are denied direct access to the internet, but the proxy does not affect user workloads.
Only cluster system egress traffic is proxied, including calls to the cloud provider API.
You can enable a proxy only for OpenShift Dedicated clusters that use the Customer Cloud Subscription (CCS) model.
If you use a cluster-wide proxy, you are responsible for maintaining the availability of the proxy to the cluster. If the proxy becomes unavailable, then it might impact the health and supportability of the cluster.
5.1. Prerequisites for configuring a cluster-wide proxy
To configure a cluster-wide proxy, you must meet the following requirements. These requirements are valid when you configure a proxy during installation or postinstallation.
General requirements
- You are the cluster owner.
- Your account has sufficient privileges.
- You have an existing Virtual Private Cloud (VPC) for your cluster.
- You are using the Customer Cloud Subscription (CCS) model for your cluster.
- The proxy can access the VPC for the cluster and the private subnets of the VPC. The proxy is also accessible from the VPC for the cluster and from the private subnets of the VPC.
You have added the following endpoints to your VPC endpoint:
-
ec2.<aws_region>.amazonaws.com
-
elasticloadbalancing.<aws_region>.amazonaws.com
s3.<aws_region>.amazonaws.com
These endpoints are required to complete requests from the nodes to the AWS EC2 API. Because the proxy works at the container level and not at the node level, you must route these requests to the AWS EC2 API through the AWS private network. Adding the public IP address of the EC2 API to your allowlist in your proxy server is not enough.
ImportantWhen using a cluster-wide proxy, you must configure the
s3.<aws_region>.amazonaws.com
endpoint as typeGateway
.
-
Network requirements
If your proxy re-encrypts egress traffic, you must create exclusions to the domain and port combinations. The following table offers guidance into these exceptions.
Your proxy must exclude re-encrypting the following OpenShift URLs:
Address Protocol/Port Function observatorium-mst.api.openshift.com
https/443
Required. Used for Managed OpenShift-specific telemetry.
sso.redhat.com
https/443
The https://cloud.redhat.com/openshift site uses authentication from sso.redhat.com to download the cluster pull secret and use Red Hat SaaS solutions to facilitate monitoring of your subscriptions, cluster inventory, and chargeback reporting.
Your proxy must exclude re-encrypting the following site reliability engineering (SRE) and management URLs:
Address Protocol/Port Function *.osdsecuritylogs.splunkcloud.com
OR
inputs1.osdsecuritylogs.splunkcloud.com
inputs2.osdsecuritylogs.splunkcloud.com
inputs4.osdsecuritylogs.splunkcloud.com
inputs5.osdsecuritylogs.splunkcloud.com
inputs6.osdsecuritylogs.splunkcloud.com
inputs7.osdsecuritylogs.splunkcloud.com
inputs8.osdsecuritylogs.splunkcloud.com
inputs9.osdsecuritylogs.splunkcloud.com
inputs10.osdsecuritylogs.splunkcloud.com
inputs11.osdsecuritylogs.splunkcloud.com
inputs12.osdsecuritylogs.splunkcloud.com
inputs13.osdsecuritylogs.splunkcloud.com
inputs14.osdsecuritylogs.splunkcloud.com
inputs15.osdsecuritylogs.splunkcloud.com
tcp/9997
Used by the splunk-forwarder-operator as a log forwarding endpoint to be used by Red Hat SRE for log-based alerting.
http-inputs-osdsecuritylogs.splunkcloud.com
https/443
Used by the splunk-forwarder-operator as a log forwarding endpoint to be used by Red Hat SRE for log-based alerting.
Additional resources
- For the installation prerequisites for OpenShift Dedicated clusters that use the Customer Cloud Subscription (CCS) model, see Customer Cloud Subscriptions on AWS or Customer Cloud Subscriptions on GCP.
5.2. Responsibilities for additional trust bundles
If you supply an additional trust bundle, you are responsible for the following requirements:
- Ensuring that the contents of the additional trust bundle are valid
- Ensuring that the certificates, including intermediary certificates, contained in the additional trust bundle have not expired
- Tracking the expiry and performing any necessary renewals for certificates contained in the additional trust bundle
- Updating the cluster configuration with the updated additional trust bundle
5.3. Configuring a proxy during installation
You can configure an HTTP or HTTPS proxy when you install an OpenShift Dedicated with Customer Cloud Subscription (CCS) cluster into an existing Virtual Private Cloud (VPC). You can configure the proxy during installation by using Red Hat OpenShift Cluster Manager.
5.4. Configuring a proxy during installation using OpenShift Cluster Manager
If you are installing an OpenShift Dedicated cluster into an existing Virtual Private Cloud (VPC), you can use Red Hat OpenShift Cluster Manager to enable a cluster-wide HTTP or HTTPS proxy during installation. You can enable a proxy only for clusters that use the Customer Cloud Subscription (CCS) model.
Prior to the installation, you must verify that the proxy is accessible from the VPC that the cluster is being installed into. The proxy must also be accessible from the private subnets of the VPC.
For detailed steps to configure a cluster-wide proxy during installation by using OpenShift Cluster Manager, see Creating a cluster on AWS with CCS or Creating a cluster on GCP with CCS.
Additional resources
5.5. Configuring a proxy after installation
You can configure an HTTP or HTTPS proxy after you install an OpenShift Dedicated with Customer Cloud Subscription (CCS) cluster into an existing Virtual Private Cloud (VPC). You can configure the proxy after installation by using Red Hat OpenShift Cluster Manager.
5.6. Configuring a proxy after installation using OpenShift Cluster Manager
You can use Red Hat OpenShift Cluster Manager to add a cluster-wide proxy configuration to an existing OpenShift Dedicated cluster in a Virtual Private Cloud (VPC). You can enable a proxy only for clusters that use the Customer Cloud Subscription (CCS) model.
You can also use OpenShift Cluster Manager to update an existing cluster-wide proxy configuration. For example, you might need to update the network address for the proxy or replace the additional trust bundle if any of the certificate authorities for the proxy expire.
The cluster applies the proxy configuration to the control plane and compute nodes. While applying the configuration, each cluster node is temporarily placed in an unschedulable state and drained of its workloads. Each node is restarted as part of the process.
Prerequisites
- You have an OpenShift Dedicated cluster that uses the Customer Cloud Subscription (CCS) model .
- Your cluster is deployed in a VPC.
Procedure
- Navigate to OpenShift Cluster Manager and select your cluster.
- Under the Virtual Private Cloud (VPC) section on the Networking page, click Edit cluster-wide proxy.
On the Edit cluster-wide proxy page, provide your proxy configuration details:
Enter a value in at least one of the following fields:
- Specify a valid HTTP proxy URL.
- Specify a valid HTTPS proxy URL.
-
In the Additional trust bundle field, provide a PEM encoded X.509 certificate bundle. If you are replacing an existing trust bundle file, select Replace file to view the field. The bundle is added to the trusted certificate store for the cluster nodes. An additional trust bundle file is required if you use a TLS-inspecting proxy unless the identity certificate for the proxy is signed by an authority from the Red Hat Enterprise Linux CoreOS (RHCOS) trust bundle. This requirement applies regardless of whether the proxy is transparent or requires explicit configuration using the
http-proxy
andhttps-proxy
arguments.
- Click Confirm.
Verification
- Under the Virtual Private Cloud (VPC) section on the Networking page, verify that the proxy configuration for your cluster is as expected.
Chapter 6. CIDR range definitions
You must specify non-overlapping ranges for the following CIDR ranges.
Machine CIDR ranges cannot be changed after creating your cluster.
When specifying subnet CIDR ranges, ensure that the subnet CIDR range is within the defined Machine CIDR. You must verify that the subnet CIDR ranges allow for enough IP addresses for all intended workloads depending on which platform the cluster is hosted.
OVN-Kubernetes, the default network provider in OpenShift Dedicated 4.14 and later versions, uses the following IP address ranges internally: 100.64.0.0/16
, 169.254.169.0/29
, 100.88.0.0/16
, fd98::/64
, fd69::/125
, and fd97::/64
. If your cluster uses OVN-Kubernetes, do not include any of these IP address ranges in any other CIDR definitions in your cluster or infrastructure.
For OpenShift Dedicated 4.17 and later versions, clusters use 169.254.0.0/17
for IPv4 and fd69::/112
for IPv6 as the default masquerade subnet. These ranges should also be avoided by users. For upgraded clusters, there is no change to the default masquerade subnet.
6.1. Machine CIDR
In the Machine classless inter-domain routing (CIDR) field, you must specify the IP address range for machines or cluster nodes. This range must encompass all CIDR address ranges for your virtual private cloud (VPC) subnets. Subnets must be contiguous. A minimum IP address range of 128 addresses, using the subnet prefix /25
, is supported for single availability zone deployments. A minimum address range of 256 addresses, using the subnet prefix /24
, is supported for deployments that use multiple availability zones.
The default is 10.0.0.0/16
. This range must not conflict with any connected networks.
6.2. Service CIDR
In the Service CIDR field, you must specify the IP address range for services. It is recommended, but not required, that the address block is the same between clusters. This will not create IP address conflicts. The range must be large enough to accommodate your workload. The address block must not overlap with any external service accessed from within the cluster. The default is 172.30.0.0/16
.
6.3. Pod CIDR
In the pod CIDR field, you must specify the IP address range for pods.
It is recommended, but not required, that the address block is the same between clusters. This will not create IP address conflicts. The range must be large enough to accommodate your workload. The address block must not overlap with any external service accessed from within the cluster. The default is 10.128.0.0/14
.
6.4. Host Prefix
In the Host Prefix field, you must specify the subnet prefix length assigned to pods scheduled to individual machines. The host prefix determines the pod IP address pool for each machine.
For example, if the host prefix is set to /23
, each machine is assigned a /23
subnet from the pod CIDR address range. The default is /23
, allowing 512 cluster nodes, and 512 pods per node (both of which are beyond our maximum supported).
Chapter 7. Network security
7.1. Understanding network policy APIs
Kubernetes offers two features that users can use to enforce network security. One feature that allows users to enforce network policy is the NetworkPolicy
API that is designed mainly for application developers and namespace tenants to protect their namespaces by creating namespace-scoped policies.
The second feature is AdminNetworkPolicy
which consists of two APIs: the AdminNetworkPolicy
(ANP) API and the BaselineAdminNetworkPolicy
(BANP) API. ANP and BANP are designed for cluster and network administrators to protect their entire cluster by creating cluster-scoped policies. Cluster administrators can use ANPs to enforce non-overridable policies that take precedence over NetworkPolicy
objects. Administrators can use BANP to set up and enforce optional cluster-scoped network policy rules that are overridable by users using NetworkPolicy
objects when necessary. When used together, ANP, BANP, and network policy can achieve full multi-tenant isolation that administrators can use to secure their cluster.
OVN-Kubernetes CNI in OpenShift Dedicated implements these network policies using Access Control List (ACL) Tiers to evaluate and apply them. ACLs are evaluated in descending order from Tier 1 to Tier 3.
Tier 1 evaluates AdminNetworkPolicy
(ANP) objects. Tier 2 evaluates NetworkPolicy
objects. Tier 3 evaluates BaselineAdminNetworkPolicy
(BANP) objects.
ANPs are evaluated first. When the match is an ANP allow
or deny
rule, any existing NetworkPolicy
and BaselineAdminNetworkPolicy
(BANP) objects in the cluster are skipped from evaluation. When the match is an ANP pass
rule, then evaluation moves from tier 1 of the ACL to tier 2 where the NetworkPolicy
policy is evaluated. If no NetworkPolicy
matches the traffic then evaluation moves from tier 2 ACLs to tier 3 ACLs where BANP is evaluated.
7.1.1. Key differences between AdminNetworkPolicy and NetworkPolicy custom resources
The following table explains key differences between the cluster scoped AdminNetworkPolicy
API and the namespace scoped NetworkPolicy
API.
Policy elements | AdminNetworkPolicy | NetworkPolicy |
---|---|---|
Applicable user | Cluster administrator or equivalent | Namespace owners |
Scope | Cluster | Namespaced |
Drop traffic |
Supported with an explicit |
Supported via implicit |
Delegate traffic |
Supported with an | Not applicable |
Allow traffic |
Supported with an explicit | The default action for all rules is to allow. |
Rule precedence within the policy | Depends on the order in which they appear within an ANP. The higher the rule’s position the higher the precedence. | Rules are additive |
Policy precedence |
Among ANPs the | There is no policy ordering between policies. |
Feature precedence | Evaluated first via tier 1 ACL and BANP is evaluated last via tier 3 ACL. | Enforced after ANP and before BANP, they are evaluated in tier 2 of the ACL. |
Matching pod selection | Can apply different rules across namespaces. | Can apply different rules across pods in single namespace. |
Cluster egress traffic |
Supported via |
Supported through |
Cluster ingress traffic | Not supported | Not supported |
Fully qualified domain names (FQDN) peer support | Not supported | Not supported |
Namespace selectors |
Supports advanced selection of Namespaces with the use of |
Supports label based namespace selection with the use of |
7.2. Network policy
7.2.1. About network policy
As a developer, you can define network policies that restrict traffic to pods in your cluster.
7.2.1.1. About network policy
By default, all pods in a project are accessible from other pods and network endpoints. To isolate one or more pods in a project, you can create NetworkPolicy
objects in that project to indicate the allowed incoming connections. Project administrators can create and delete NetworkPolicy
objects within their own project.
If a pod is matched by selectors in one or more NetworkPolicy
objects, then the pod will accept only connections that are allowed by at least one of those NetworkPolicy
objects. A pod that is not selected by any NetworkPolicy
objects is fully accessible.
A network policy applies to only the TCP, UDP, ICMP, and SCTP protocols. Other protocols are not affected.
Network policy does not apply to the host network namespace. Pods with host networking enabled are unaffected by network policy rules. However, pods connecting to the host-networked pods might be affected by the network policy rules.
Network policies cannot block traffic from localhost or from their resident nodes.
The following example NetworkPolicy
objects demonstrate supporting different scenarios:
Deny all traffic:
To make a project deny by default, add a
NetworkPolicy
object that matches all pods but accepts no traffic:kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: deny-by-default spec: podSelector: {} ingress: []
Only allow connections from the OpenShift Dedicated Ingress Controller:
To make a project allow only connections from the OpenShift Dedicated Ingress Controller, add the following
NetworkPolicy
object.apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: allow-from-openshift-ingress spec: ingress: - from: - namespaceSelector: matchLabels: network.openshift.io/policy-group: ingress podSelector: {} policyTypes: - Ingress
Only accept connections from pods within a project:
ImportantTo allow ingress connections from
hostNetwork
pods in the same namespace, you need to apply theallow-from-hostnetwork
policy together with theallow-same-namespace
policy.To make pods accept connections from other pods in the same project, but reject all other connections from pods in other projects, add the following
NetworkPolicy
object:kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: allow-same-namespace spec: podSelector: {} ingress: - from: - podSelector: {}
Only allow HTTP and HTTPS traffic based on pod labels:
To enable only HTTP and HTTPS access to the pods with a specific label (
role=frontend
in following example), add aNetworkPolicy
object similar to the following:kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: allow-http-and-https spec: podSelector: matchLabels: role: frontend ingress: - ports: - protocol: TCP port: 80 - protocol: TCP port: 443
Accept connections by using both namespace and pod selectors:
To match network traffic by combining namespace and pod selectors, you can use a
NetworkPolicy
object similar to the following:kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: allow-pod-and-namespace-both spec: podSelector: matchLabels: name: test-pods ingress: - from: - namespaceSelector: matchLabels: project: project_name podSelector: matchLabels: name: test-pods
NetworkPolicy
objects are additive, which means you can combine multiple NetworkPolicy
objects together to satisfy complex network requirements.
For example, for the NetworkPolicy
objects defined in previous samples, you can define both allow-same-namespace
and allow-http-and-https
policies within the same project. Thus allowing the pods with the label role=frontend
, to accept any connection allowed by each policy. That is, connections on any port from pods in the same namespace, and connections on ports 80
and 443
from pods in any namespace.
7.2.1.1.1. Using the allow-from-router network policy
Use the following NetworkPolicy
to allow external traffic regardless of the router configuration:
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: allow-from-router
spec:
ingress:
- from:
- namespaceSelector:
matchLabels:
policy-group.network.openshift.io/ingress: ""1
podSelector: {}
policyTypes:
- Ingress
- 1
policy-group.network.openshift.io/ingress:""
label supports OVN-Kubernetes.
7.2.1.1.2. Using the allow-from-hostnetwork network policy
Add the following allow-from-hostnetwork
NetworkPolicy
object to direct traffic from the host network pods.
apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: allow-from-hostnetwork spec: ingress: - from: - namespaceSelector: matchLabels: policy-group.network.openshift.io/host-network: "" podSelector: {} policyTypes: - Ingress
7.2.1.2. Optimizations for network policy with OVN-Kubernetes network plugin
When designing your network policy, refer to the following guidelines:
-
For network policies with the same
spec.podSelector
spec, it is more efficient to use one network policy with multipleingress
oregress
rules, than multiple network policies with subsets ofingress
oregress
rules. Every
ingress
oregress
rule based on thepodSelector
ornamespaceSelector
spec generates the number of OVS flows proportional tonumber of pods selected by network policy + number of pods selected by ingress or egress rule
. Therefore, it is preferable to use thepodSelector
ornamespaceSelector
spec that can select as many pods as you need in one rule, instead of creating individual rules for every pod.For example, the following policy contains two rules:
apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: test-network-policy spec: podSelector: {} ingress: - from: - podSelector: matchLabels: role: frontend - from: - podSelector: matchLabels: role: backend
The following policy expresses those same two rules as one:
apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: test-network-policy spec: podSelector: {} ingress: - from: - podSelector: matchExpressions: - {key: role, operator: In, values: [frontend, backend]}
The same guideline applies to the
spec.podSelector
spec. If you have the sameingress
oregress
rules for different network policies, it might be more efficient to create one network policy with a commonspec.podSelector
spec. For example, the following two policies have different rules:apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: policy1 spec: podSelector: matchLabels: role: db ingress: - from: - podSelector: matchLabels: role: frontend --- apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: policy2 spec: podSelector: matchLabels: role: client ingress: - from: - podSelector: matchLabels: role: frontend
The following network policy expresses those same two rules as one:
apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: policy3 spec: podSelector: matchExpressions: - {key: role, operator: In, values: [db, client]} ingress: - from: - podSelector: matchLabels: role: frontend
You can apply this optimization when only multiple selectors are expressed as one. In cases where selectors are based on different labels, it may not be possible to apply this optimization. In those cases, consider applying some new labels for network policy optimization specifically.
7.2.1.3. Next steps
7.2.2. Creating a network policy
As a user with the admin
role, you can create a network policy for a namespace.
7.2.2.1. Example NetworkPolicy object
The following annotates an example NetworkPolicy object:
kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: allow-27107 1 spec: podSelector: 2 matchLabels: app: mongodb ingress: - from: - podSelector: 3 matchLabels: app: app ports: 4 - protocol: TCP port: 27017
- 1
- The name of the NetworkPolicy object.
- 2
- A selector that describes the pods to which the policy applies. The policy object can only select pods in the project that defines the NetworkPolicy object.
- 3
- A selector that matches the pods from which the policy object allows ingress traffic. The selector matches pods in the same namespace as the NetworkPolicy.
- 4
- A list of one or more destination ports on which to accept traffic.
7.2.2.2. Creating a network policy using the CLI
To define granular rules describing ingress or egress network traffic allowed for namespaces in your cluster, you can create a network policy.
If you log in with a user with the cluster-admin
role, then you can create a network policy in any namespace in the cluster.
Prerequisites
-
Your cluster uses a network plugin that supports
NetworkPolicy
objects, such as the OVN-Kubernetes network plugin, withmode: NetworkPolicy
set. -
You installed the OpenShift CLI (
oc
). -
You are logged in to the cluster with a user with
admin
privileges. - You are working in the namespace that the network policy applies to.
Procedure
Create a policy rule:
Create a
<policy_name>.yaml
file:$ touch <policy_name>.yaml
where:
<policy_name>
- Specifies the network policy file name.
Define a network policy in the file that you just created, such as in the following examples:
Deny ingress from all pods in all namespaces
This is a fundamental policy, blocking all cross-pod networking other than cross-pod traffic allowed by the configuration of other Network Policies.
kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: deny-by-default spec: podSelector: {} policyTypes: - Ingress ingress: []
Allow ingress from all pods in the same namespace
kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: allow-same-namespace spec: podSelector: ingress: - from: - podSelector: {}
Allow ingress traffic to one pod from a particular namespace
This policy allows traffic to pods labelled
pod-a
from pods running innamespace-y
.kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: allow-traffic-pod spec: podSelector: matchLabels: pod: pod-a policyTypes: - Ingress ingress: - from: - namespaceSelector: matchLabels: kubernetes.io/metadata.name: namespace-y
To create the network policy object, enter the following command:
$ oc apply -f <policy_name>.yaml -n <namespace>
where:
<policy_name>
- Specifies the network policy file name.
<namespace>
- Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.
Example output
networkpolicy.networking.k8s.io/deny-by-default created
If you log in to the web console with cluster-admin
privileges, you have a choice of creating a network policy in any namespace in the cluster directly in YAML or from a form in the web console.
7.2.2.3. Creating a default deny all network policy
This is a fundamental policy, blocking all cross-pod networking other than network traffic allowed by the configuration of other deployed network policies. This procedure enforces a default deny-by-default
policy.
If you log in with a user with the cluster-admin
role, then you can create a network policy in any namespace in the cluster.
Prerequisites
-
Your cluster uses a network plugin that supports
NetworkPolicy
objects, such as the OVN-Kubernetes network plugin, withmode: NetworkPolicy
set. -
You installed the OpenShift CLI (
oc
). -
You are logged in to the cluster with a user with
admin
privileges. - You are working in the namespace that the network policy applies to.
Procedure
Create the following YAML that defines a
deny-by-default
policy to deny ingress from all pods in all namespaces. Save the YAML in thedeny-by-default.yaml
file:kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: deny-by-default namespace: default 1 spec: podSelector: {} 2 ingress: [] 3
Apply the policy by entering the following command:
$ oc apply -f deny-by-default.yaml
Example output
networkpolicy.networking.k8s.io/deny-by-default created
7.2.2.4. Creating a network policy to allow traffic from external clients
With the deny-by-default
policy in place you can proceed to configure a policy that allows traffic from external clients to a pod with the label app=web
.
If you log in with a user with the cluster-admin
role, then you can create a network policy in any namespace in the cluster.
Follow this procedure to configure a policy that allows external service from the public Internet directly or by using a Load Balancer to access the pod. Traffic is only allowed to a pod with the label app=web
.
Prerequisites
-
Your cluster uses a network plugin that supports
NetworkPolicy
objects, such as the OVN-Kubernetes network plugin, withmode: NetworkPolicy
set. -
You installed the OpenShift CLI (
oc
). -
You are logged in to the cluster with a user with
admin
privileges. - You are working in the namespace that the network policy applies to.
Procedure
Create a policy that allows traffic from the public Internet directly or by using a load balancer to access the pod. Save the YAML in the
web-allow-external.yaml
file:kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: web-allow-external namespace: default spec: policyTypes: - Ingress podSelector: matchLabels: app: web ingress: - {}
Apply the policy by entering the following command:
$ oc apply -f web-allow-external.yaml
Example output
networkpolicy.networking.k8s.io/web-allow-external created
This policy allows traffic from all resources, including external traffic as illustrated in the following diagram:
7.2.2.5. Creating a network policy allowing traffic to an application from all namespaces
If you log in with a user with the cluster-admin
role, then you can create a network policy in any namespace in the cluster.
Follow this procedure to configure a policy that allows traffic from all pods in all namespaces to a particular application.
Prerequisites
-
Your cluster uses a network plugin that supports
NetworkPolicy
objects, such as the OVN-Kubernetes network plugin, withmode: NetworkPolicy
set. -
You installed the OpenShift CLI (
oc
). -
You are logged in to the cluster with a user with
admin
privileges. - You are working in the namespace that the network policy applies to.
Procedure
Create a policy that allows traffic from all pods in all namespaces to a particular application. Save the YAML in the
web-allow-all-namespaces.yaml
file:kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: web-allow-all-namespaces namespace: default spec: podSelector: matchLabels: app: web 1 policyTypes: - Ingress ingress: - from: - namespaceSelector: {} 2
NoteBy default, if you omit specifying a
namespaceSelector
it does not select any namespaces, which means the policy allows traffic only from the namespace the network policy is deployed to.Apply the policy by entering the following command:
$ oc apply -f web-allow-all-namespaces.yaml
Example output
networkpolicy.networking.k8s.io/web-allow-all-namespaces created
Verification
Start a web service in the
default
namespace by entering the following command:$ oc run web --namespace=default --image=nginx --labels="app=web" --expose --port=80
Run the following command to deploy an
alpine
image in thesecondary
namespace and to start a shell:$ oc run test-$RANDOM --namespace=secondary --rm -i -t --image=alpine -- sh
Run the following command in the shell and observe that the request is allowed:
# wget -qO- --timeout=2 http://web.default
Expected output
<!DOCTYPE html> <html> <head> <title>Welcome to nginx!</title> <style> html { color-scheme: light dark; } body { width: 35em; margin: 0 auto; font-family: Tahoma, Verdana, Arial, sans-serif; } </style> </head> <body> <h1>Welcome to nginx!</h1> <p>If you see this page, the nginx web server is successfully installed and working. Further configuration is required.</p> <p>For online documentation and support please refer to <a href="http://nginx.org/">nginx.org</a>.<br/> Commercial support is available at <a href="http://nginx.com/">nginx.com</a>.</p> <p><em>Thank you for using nginx.</em></p> </body> </html>
7.2.2.6. Creating a network policy allowing traffic to an application from a namespace
If you log in with a user with the cluster-admin
role, then you can create a network policy in any namespace in the cluster.
Follow this procedure to configure a policy that allows traffic to a pod with the label app=web
from a particular namespace. You might want to do this to:
- Restrict traffic to a production database only to namespaces where production workloads are deployed.
- Enable monitoring tools deployed to a particular namespace to scrape metrics from the current namespace.
Prerequisites
-
Your cluster uses a network plugin that supports
NetworkPolicy
objects, such as the OVN-Kubernetes network plugin, withmode: NetworkPolicy
set. -
You installed the OpenShift CLI (
oc
). -
You are logged in to the cluster with a user with
admin
privileges. - You are working in the namespace that the network policy applies to.
Procedure
Create a policy that allows traffic from all pods in a particular namespaces with a label
purpose=production
. Save the YAML in theweb-allow-prod.yaml
file:kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: web-allow-prod namespace: default spec: podSelector: matchLabels: app: web 1 policyTypes: - Ingress ingress: - from: - namespaceSelector: matchLabels: purpose: production 2
Apply the policy by entering the following command:
$ oc apply -f web-allow-prod.yaml
Example output
networkpolicy.networking.k8s.io/web-allow-prod created
Verification
Start a web service in the
default
namespace by entering the following command:$ oc run web --namespace=default --image=nginx --labels="app=web" --expose --port=80
Run the following command to create the
prod
namespace:$ oc create namespace prod
Run the following command to label the
prod
namespace:$ oc label namespace/prod purpose=production
Run the following command to create the
dev
namespace:$ oc create namespace dev
Run the following command to label the
dev
namespace:$ oc label namespace/dev purpose=testing
Run the following command to deploy an
alpine
image in thedev
namespace and to start a shell:$ oc run test-$RANDOM --namespace=dev --rm -i -t --image=alpine -- sh
Run the following command in the shell and observe that the request is blocked:
# wget -qO- --timeout=2 http://web.default
Expected output
wget: download timed out
Run the following command to deploy an
alpine
image in theprod
namespace and start a shell:$ oc run test-$RANDOM --namespace=prod --rm -i -t --image=alpine -- sh
Run the following command in the shell and observe that the request is allowed:
# wget -qO- --timeout=2 http://web.default
Expected output
<!DOCTYPE html> <html> <head> <title>Welcome to nginx!</title> <style> html { color-scheme: light dark; } body { width: 35em; margin: 0 auto; font-family: Tahoma, Verdana, Arial, sans-serif; } </style> </head> <body> <h1>Welcome to nginx!</h1> <p>If you see this page, the nginx web server is successfully installed and working. Further configuration is required.</p> <p>For online documentation and support please refer to <a href="http://nginx.org/">nginx.org</a>.<br/> Commercial support is available at <a href="http://nginx.com/">nginx.com</a>.</p> <p><em>Thank you for using nginx.</em></p> </body> </html>
7.2.2.7. Creating a network policy using OpenShift Cluster Manager
To define granular rules describing the ingress or egress network traffic allowed for namespaces in your cluster, you can create a network policy.
Prerequisites
- You logged in to OpenShift Cluster Manager.
- You created an OpenShift Dedicated cluster.
- You configured an identity provider for your cluster.
- You added your user account to the configured identity provider.
- You created a project within your OpenShift Dedicated cluster.
Procedure
- From OpenShift Cluster Manager, click on the cluster you want to access.
- Click Open console to navigate to the OpenShift web console.
- Click on your identity provider and provide your credentials to log in to the cluster.
- From the administrator perspective, under Networking, click NetworkPolicies.
- Click Create NetworkPolicy.
- Provide a name for the policy in the Policy name field.
- Optional: You can provide the label and selector for a specific pod if this policy applies only to one or more specific pods. If you do not select a specific pod, then this policy will be applicable to all pods on the cluster.
- Optional: You can block all ingress and egress traffic by using the Deny all ingress traffic or Deny all egress traffic checkboxes.
- You can also add any combination of ingress and egress rules, allowing you to specify the port, namespace, or IP blocks you want to approve.
Add ingress rules to your policy:
Select Add ingress rule to configure a new rule. This action creates a new Ingress rule row with an Add allowed source drop-down menu that enables you to specify how you want to limit inbound traffic. The drop-down menu offers three options to limit your ingress traffic:
- Allow pods from the same namespace limits traffic to pods within the same namespace. You can specify the pods in a namespace, but leaving this option blank allows all of the traffic from pods in the namespace.
- Allow pods from inside the cluster limits traffic to pods within the same cluster as the policy. You can specify namespaces and pods from which you want to allow inbound traffic. Leaving this option blank allows inbound traffic from all namespaces and pods within this cluster.
- Allow peers by IP block limits traffic from a specified Classless Inter-Domain Routing (CIDR) IP block. You can block certain IPs with the exceptions option. Leaving the CIDR field blank allows all inbound traffic from all external sources.
- You can restrict all of your inbound traffic to a port. If you do not add any ports then all ports are accessible to traffic.
Add egress rules to your network policy:
Select Add egress rule to configure a new rule. This action creates a new Egress rule row with an Add allowed destination"* drop-down menu that enables you to specify how you want to limit outbound traffic. The drop-down menu offers three options to limit your egress traffic:
- Allow pods from the same namespace limits outbound traffic to pods within the same namespace. You can specify the pods in a namespace, but leaving this option blank allows all of the traffic from pods in the namespace.
- Allow pods from inside the cluster limits traffic to pods within the same cluster as the policy. You can specify namespaces and pods from which you want to allow outbound traffic. Leaving this option blank allows outbound traffic from all namespaces and pods within this cluster.
- Allow peers by IP block limits traffic from a specified CIDR IP block. You can block certain IPs with the exceptions option. Leaving the CIDR field blank allows all outbound traffic from all external sources.
- You can restrict all of your outbound traffic to a port. If you do not add any ports then all ports are accessible to traffic.
7.2.3. Viewing a network policy
As a user with the admin
role, you can view a network policy for a namespace.
7.2.3.1. Example NetworkPolicy object
The following annotates an example NetworkPolicy object:
kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: allow-27107 1 spec: podSelector: 2 matchLabels: app: mongodb ingress: - from: - podSelector: 3 matchLabels: app: app ports: 4 - protocol: TCP port: 27017
- 1
- The name of the NetworkPolicy object.
- 2
- A selector that describes the pods to which the policy applies. The policy object can only select pods in the project that defines the NetworkPolicy object.
- 3
- A selector that matches the pods from which the policy object allows ingress traffic. The selector matches pods in the same namespace as the NetworkPolicy.
- 4
- A list of one or more destination ports on which to accept traffic.
7.2.3.2. Viewing network policies using the CLI
You can examine the network policies in a namespace.
If you log in with a user with the cluster-admin
role, then you can view any network policy in the cluster.
Prerequisites
-
You installed the OpenShift CLI (
oc
). -
You are logged in to the cluster with a user with
admin
privileges. - You are working in the namespace where the network policy exists.
Procedure
List network policies in a namespace:
To view network policy objects defined in a namespace, enter the following command:
$ oc get networkpolicy
Optional: To examine a specific network policy, enter the following command:
$ oc describe networkpolicy <policy_name> -n <namespace>
where:
<policy_name>
- Specifies the name of the network policy to inspect.
<namespace>
- Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.
For example:
$ oc describe networkpolicy allow-same-namespace
Output for
oc describe
commandName: allow-same-namespace Namespace: ns1 Created on: 2021-05-24 22:28:56 -0400 EDT Labels: <none> Annotations: <none> Spec: PodSelector: <none> (Allowing the specific traffic to all pods in this namespace) Allowing ingress traffic: To Port: <any> (traffic allowed to all ports) From: PodSelector: <none> Not affecting egress traffic Policy Types: Ingress
If you log in to the web console with cluster-admin
privileges, you have a choice of viewing a network policy in any namespace in the cluster directly in YAML or from a form in the web console.
7.2.3.3. Viewing network policies using OpenShift Cluster Manager
You can view the configuration details of your network policy in Red Hat OpenShift Cluster Manager.
Prerequisites
- You logged in to OpenShift Cluster Manager.
- You created an OpenShift Dedicated cluster.
- You configured an identity provider for your cluster.
- You added your user account to the configured identity provider.
- You created a network policy.
Procedure
- From the Administrator perspective in the OpenShift Cluster Manager web console, under Networking, click NetworkPolicies.
- Select the desired network policy to view.
- In the Network Policy details page, you can view all of the associated ingress and egress rules.
Select YAML on the network policy details to view the policy configuration in YAML format.
NoteYou can only view the details of these policies. You cannot edit these policies.
7.2.4. Deleting a network policy
As a user with the admin
role, you can delete a network policy from a namespace.
7.2.4.1. Deleting a network policy using the CLI
You can delete a network policy in a namespace.
If you log in with a user with the cluster-admin
role, then you can delete any network policy in the cluster.
Prerequisites
-
Your cluster uses a network plugin that supports
NetworkPolicy
objects, such as the OVN-Kubernetes network plugin, withmode: NetworkPolicy
set. -
You installed the OpenShift CLI (
oc
). -
You are logged in to the cluster with a user with
admin
privileges. - You are working in the namespace where the network policy exists.
Procedure
To delete a network policy object, enter the following command:
$ oc delete networkpolicy <policy_name> -n <namespace>
where:
<policy_name>
- Specifies the name of the network policy.
<namespace>
- Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.
Example output
networkpolicy.networking.k8s.io/default-deny deleted
If you log in to the web console with cluster-admin
privileges, you have a choice of deleting a network policy in any namespace in the cluster directly in YAML or from the policy in the web console through the Actions menu.
7.2.4.2. Deleting a network policy using OpenShift Cluster Manager
You can delete a network policy in a namespace.
Prerequisites
- You logged in to OpenShift Cluster Manager.
- You created an OpenShift Dedicated cluster.
- You configured an identity provider for your cluster.
- You added your user account to the configured identity provider.
Procedure
- From the Administrator perspective in the OpenShift Cluster Manager web console, under Networking, click NetworkPolicies.
Use one of the following methods for deleting your network policy:
Delete the policy from the Network Policies table:
- From the Network Policies table, select the stack menu on the row of the network policy you want to delete and then, click Delete NetworkPolicy.
Delete the policy using the Actions drop-down menu from the individual network policy details:
- Click on Actions drop-down menu for your network policy.
- Select Delete NetworkPolicy from the menu.
7.2.5. Configuring multitenant isolation with network policy
As a cluster administrator, you can configure your network policies to provide multitenant network isolation.
Configuring network policies as described in this section provides network isolation similar to the multitenant mode of OpenShift SDN in previous versions of OpenShift Dedicated.
7.2.5.1. Configuring multitenant isolation by using network policy
You can configure your project to isolate it from pods and services in other project namespaces.
Prerequisites
-
Your cluster uses a network plugin that supports
NetworkPolicy
objects, such as the OVN-Kubernetes network plugin, withmode: NetworkPolicy
set. -
You installed the OpenShift CLI (
oc
). -
You are logged in to the cluster with a user with
admin
privileges.
Procedure
Create the following
NetworkPolicy
objects:A policy named
allow-from-openshift-ingress
.$ cat << EOF| oc create -f - apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: allow-from-openshift-ingress spec: ingress: - from: - namespaceSelector: matchLabels: policy-group.network.openshift.io/ingress: "" podSelector: {} policyTypes: - Ingress EOF
Notepolicy-group.network.openshift.io/ingress: ""
is the preferred namespace selector label for OVN-Kubernetes.A policy named
allow-from-openshift-monitoring
:$ cat << EOF| oc create -f - apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: allow-from-openshift-monitoring spec: ingress: - from: - namespaceSelector: matchLabels: network.openshift.io/policy-group: monitoring podSelector: {} policyTypes: - Ingress EOF
A policy named
allow-same-namespace
:$ cat << EOF| oc create -f - kind: NetworkPolicy apiVersion: networking.k8s.io/v1 metadata: name: allow-same-namespace spec: podSelector: ingress: - from: - podSelector: {} EOF
A policy named
allow-from-kube-apiserver-operator
:$ cat << EOF| oc create -f - apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: name: allow-from-kube-apiserver-operator spec: ingress: - from: - namespaceSelector: matchLabels: kubernetes.io/metadata.name: openshift-kube-apiserver-operator podSelector: matchLabels: app: kube-apiserver-operator policyTypes: - Ingress EOF
For more details, see New
kube-apiserver-operator
webhook controller validating health of webhook.
Optional: To confirm that the network policies exist in your current project, enter the following command:
$ oc describe networkpolicy
Example output
Name: allow-from-openshift-ingress Namespace: example1 Created on: 2020-06-09 00:28:17 -0400 EDT Labels: <none> Annotations: <none> Spec: PodSelector: <none> (Allowing the specific traffic to all pods in this namespace) Allowing ingress traffic: To Port: <any> (traffic allowed to all ports) From: NamespaceSelector: network.openshift.io/policy-group: ingress Not affecting egress traffic Policy Types: Ingress Name: allow-from-openshift-monitoring Namespace: example1 Created on: 2020-06-09 00:29:57 -0400 EDT Labels: <none> Annotations: <none> Spec: PodSelector: <none> (Allowing the specific traffic to all pods in this namespace) Allowing ingress traffic: To Port: <any> (traffic allowed to all ports) From: NamespaceSelector: network.openshift.io/policy-group: monitoring Not affecting egress traffic Policy Types: Ingress
Chapter 8. OVN-Kubernetes network plugin
8.1. About the OVN-Kubernetes network plugin
The OpenShift Dedicated cluster uses a virtualized network for pod and service networks.
Part of Red Hat OpenShift Networking, the OVN-Kubernetes network plugin is the default network provider for OpenShift Dedicated. OVN-Kubernetes is based on Open Virtual Network (OVN) and provides an overlay-based networking implementation. A cluster that uses the OVN-Kubernetes plugin also runs Open vSwitch (OVS) on each node. OVN configures OVS on each node to implement the declared network configuration.
OVN-Kubernetes is the default networking solution for OpenShift Dedicated and single-node OpenShift deployments.
OVN-Kubernetes, which arose from the OVS project, uses many of the same constructs, such as open flow rules, to determine how packets travel through the network. For more information, see the Open Virtual Network website.
OVN-Kubernetes is a series of daemons for OVS that translate virtual network configurations into OpenFlow
rules. OpenFlow
is a protocol for communicating with network switches and routers, providing a means for remotely controlling the flow of network traffic on a network device so that network administrators can configure, manage, and monitor the flow of network traffic.
OVN-Kubernetes provides more of the advanced functionality not available with OpenFlow
. OVN supports distributed virtual routing, distributed logical switches, access control, Dynamic Host Configuration Protocol (DHCP), and DNS. OVN implements distributed virtual routing within logic flows that equate to open flows. For example, if you have a pod that sends out a DHCP request to the DHCP server on the network, a logic flow rule in the request helps the OVN-Kubernetes handle the packet so that the server can respond with gateway, DNS server, IP address, and other information.
OVN-Kubernetes runs a daemon on each node. There are daemon sets for the databases and for the OVN controller that run on every node. The OVN controller programs the Open vSwitch daemon on the nodes to support the network provider features: egress IPs, firewalls, routers, hybrid networking, IPSEC encryption, IPv6, network policy, network policy logs, hardware offloading, and multicast.
8.1.1. OVN-Kubernetes purpose
The OVN-Kubernetes network plugin is an open-source, fully-featured Kubernetes CNI plugin that uses Open Virtual Network (OVN) to manage network traffic flows. OVN is a community developed, vendor-agnostic network virtualization solution. The OVN-Kubernetes network plugin uses the following technologies:
- OVN to manage network traffic flows.
- Kubernetes network policy support and logs, including ingress and egress rules.
- The Generic Network Virtualization Encapsulation (Geneve) protocol, rather than Virtual Extensible LAN (VXLAN), to create an overlay network between nodes.
The OVN-Kubernetes network plugin supports the following capabilities:
- Hybrid clusters that can run both Linux and Microsoft Windows workloads. This environment is known as hybrid networking.
- Offloading of network data processing from the host central processing unit (CPU) to compatible network cards and data processing units (DPUs). This is known as hardware offloading.
- IPv4-primary dual-stack networking on bare-metal, VMware vSphere, IBM Power®, IBM Z®, and RHOSP platforms.
- IPv6 single-stack networking on a bare-metal platform.
- IPv6-primary dual-stack networking for a cluster running on a bare-metal, a VMware vSphere, or an RHOSP platform.
- Egress firewall devices and egress IP addresses.
- Egress router devices that operate in redirect mode.
- IPsec encryption of intracluster communications.
8.1.2. OVN-Kubernetes IPv6 and dual-stack limitations
The OVN-Kubernetes network plugin has the following limitations:
For clusters configured for dual-stack networking, both IPv4 and IPv6 traffic must use the same network interface as the default gateway. If this requirement is not met, pods on the host in the
ovnkube-node
daemon set enter theCrashLoopBackOff
state. If you display a pod with a command such asoc get pod -n openshift-ovn-kubernetes -l app=ovnkube-node -o yaml
, thestatus
field contains more than one message about the default gateway, as shown in the following output:I1006 16:09:50.985852 60651 helper_linux.go:73] Found default gateway interface br-ex 192.168.127.1 I1006 16:09:50.985923 60651 helper_linux.go:73] Found default gateway interface ens4 fe80::5054:ff:febe:bcd4 F1006 16:09:50.985939 60651 ovnkube.go:130] multiple gateway interfaces detected: br-ex ens4
The only resolution is to reconfigure the host networking so that both IP families use the same network interface for the default gateway.
For clusters configured for dual-stack networking, both the IPv4 and IPv6 routing tables must contain the default gateway. If this requirement is not met, pods on the host in the
ovnkube-node
daemon set enter theCrashLoopBackOff
state. If you display a pod with a command such asoc get pod -n openshift-ovn-kubernetes -l app=ovnkube-node -o yaml
, thestatus
field contains more than one message about the default gateway, as shown in the following output:I0512 19:07:17.589083 108432 helper_linux.go:74] Found default gateway interface br-ex 192.168.123.1 F0512 19:07:17.589141 108432 ovnkube.go:133] failed to get default gateway interface
The only resolution is to reconfigure the host networking so that both IP families contain the default gateway.
8.1.3. Session affinity
Session affinity is a feature that applies to Kubernetes Service
objects. You can use session affinity if you want to ensure that each time you connect to a <service_VIP>:<Port>, the traffic is always load balanced to the same back end. For more information, including how to set session affinity based on a client’s IP address, see Session affinity.
Stickiness timeout for session affinity
The OVN-Kubernetes network plugin for OpenShift Dedicated calculates the stickiness timeout for a session from a client based on the last packet. For example, if you run a curl
command 10 times, the sticky session timer starts from the tenth packet not the first. As a result, if the client is continuously contacting the service, then the session never times out. The timeout starts when the service has not received a packet for the amount of time set by the timeoutSeconds
parameter.
Chapter 9. OpenShift SDN network plugin
9.1. Enabling multicast for a project
9.1.1. About multicast
With IP multicast, data is broadcast to many IP addresses simultaneously.
- At this time, multicast is best used for low-bandwidth coordination or service discovery and not a high-bandwidth solution.
-
By default, network policies affect all connections in a namespace. However, multicast is unaffected by network policies. If multicast is enabled in the same namespace as your network policies, it is always allowed, even if there is a
deny-all
network policy. Cluster administrators should consider the implications to the exemption of multicast from network policies before enabling it.
Multicast traffic between OpenShift Dedicated pods is disabled by default. If you are using the OVN-Kubernetes network plugin, you can enable multicast on a per-project basis.
9.1.2. Enabling multicast between pods
You can enable multicast between pods for your project.
Prerequisites
-
Install the OpenShift CLI (
oc
). -
You must log in to the cluster with a user that has the
cluster-admin
or thededicated-admin
role.
Procedure
Run the following command to enable multicast for a project. Replace
<namespace>
with the namespace for the project you want to enable multicast for.$ oc annotate namespace <namespace> \ k8s.ovn.org/multicast-enabled=true
TipYou can alternatively apply the following YAML to add the annotation:
apiVersion: v1 kind: Namespace metadata: name: <namespace> annotations: k8s.ovn.org/multicast-enabled: "true"
Verification
To verify that multicast is enabled for a project, complete the following procedure:
Change your current project to the project that you enabled multicast for. Replace
<project>
with the project name.$ oc project <project>
Create a pod to act as a multicast receiver:
$ cat <<EOF| oc create -f - apiVersion: v1 kind: Pod metadata: name: mlistener labels: app: multicast-verify spec: containers: - name: mlistener image: registry.access.redhat.com/ubi9 command: ["/bin/sh", "-c"] args: ["dnf -y install socat hostname && sleep inf"] ports: - containerPort: 30102 name: mlistener protocol: UDP EOF
Create a pod to act as a multicast sender:
$ cat <<EOF| oc create -f - apiVersion: v1 kind: Pod metadata: name: msender labels: app: multicast-verify spec: containers: - name: msender image: registry.access.redhat.com/ubi9 command: ["/bin/sh", "-c"] args: ["dnf -y install socat && sleep inf"] EOF
In a new terminal window or tab, start the multicast listener.
Get the IP address for the Pod:
$ POD_IP=$(oc get pods mlistener -o jsonpath='{.status.podIP}')
Start the multicast listener by entering the following command:
$ oc exec mlistener -i -t -- \ socat UDP4-RECVFROM:30102,ip-add-membership=224.1.0.1:$POD_IP,fork EXEC:hostname
Start the multicast transmitter.
Get the pod network IP address range:
$ CIDR=$(oc get Network.config.openshift.io cluster \ -o jsonpath='{.status.clusterNetwork[0].cidr}')
To send a multicast message, enter the following command:
$ oc exec msender -i -t -- \ /bin/bash -c "echo | socat STDIO UDP4-DATAGRAM:224.1.0.1:30102,range=$CIDR,ip-multicast-ttl=64"
If multicast is working, the previous command returns the following output:
mlistener
Chapter 10. Configuring Routes
10.1. Route configuration
10.1.1. Creating an HTTP-based route
A route allows you to host your application at a public URL. It can either be secure or unsecured, depending on the network security configuration of your application. An HTTP-based route is an unsecured route that uses the basic HTTP routing protocol and exposes a service on an unsecured application port.
The following procedure describes how to create a simple HTTP-based route to a web application, using the hello-openshift
application as an example.
Prerequisites
-
You installed the OpenShift CLI (
oc
). - You are logged in as an administrator.
- You have a web application that exposes a port and a TCP endpoint listening for traffic on the port.
Procedure
Create a project called
hello-openshift
by running the following command:$ oc new-project hello-openshift
Create a pod in the project by running the following command:
$ oc create -f https://raw.githubusercontent.com/openshift/origin/master/examples/hello-openshift/hello-pod.json
Create a service called
hello-openshift
by running the following command:$ oc expose pod/hello-openshift
Create an unsecured route to the
hello-openshift
application by running the following command:$ oc expose svc hello-openshift
Verification
To verify that the
route
resource that you created, run the following command:$ oc get routes -o yaml <name of resource> 1
- 1
- In this example, the route is named
hello-openshift
.
Sample YAML definition of the created unsecured route
apiVersion: route.openshift.io/v1 kind: Route metadata: name: hello-openshift spec: host: hello-openshift-hello-openshift.<Ingress_Domain> 1 port: targetPort: 8080 2 to: kind: Service name: hello-openshift
- 1
<Ingress_Domain>
is the default ingress domain name. Theingresses.config/cluster
object is created during the installation and cannot be changed. If you want to specify a different domain, you can specify an alternative cluster domain using theappsDomain
option.- 2
targetPort
is the target port on pods that is selected by the service that this route points to.NoteTo display your default ingress domain, run the following command:
$ oc get ingresses.config/cluster -o jsonpath={.spec.domain}
10.1.2. Configuring route timeouts
You can configure the default timeouts for an existing route when you have services in need of a low timeout, which is required for Service Level Availability (SLA) purposes, or a high timeout, for cases with a slow back end.
Prerequisites
- You need a deployed Ingress Controller on a running cluster.
Procedure
Using the
oc annotate
command, add the timeout to the route:$ oc annotate route <route_name> \ --overwrite haproxy.router.openshift.io/timeout=<timeout><time_unit> 1
- 1
- Supported time units are microseconds (us), milliseconds (ms), seconds (s), minutes (m), hours (h), or days (d).
The following example sets a timeout of two seconds on a route named
myroute
:$ oc annotate route myroute --overwrite haproxy.router.openshift.io/timeout=2s
10.1.3. HTTP Strict Transport Security
HTTP Strict Transport Security (HSTS) policy is a security enhancement, which signals to the browser client that only HTTPS traffic is allowed on the route host. HSTS also optimizes web traffic by signaling HTTPS transport is required, without using HTTP redirects. HSTS is useful for speeding up interactions with websites.
When HSTS policy is enforced, HSTS adds a Strict Transport Security header to HTTP and HTTPS responses from the site. You can use the insecureEdgeTerminationPolicy
value in a route to redirect HTTP to HTTPS. When HSTS is enforced, the client changes all requests from the HTTP URL to HTTPS before the request is sent, eliminating the need for a redirect.
Cluster administrators can configure HSTS to do the following:
- Enable HSTS per-route
- Disable HSTS per-route
- Enforce HSTS per-domain, for a set of domains, or use namespace labels in combination with domains
HSTS works only with secure routes, either edge-terminated or re-encrypt. The configuration is ineffective on HTTP or passthrough routes.
10.1.3.1. Enabling HTTP Strict Transport Security per-route
HTTP strict transport security (HSTS) is implemented in the HAProxy template and applied to edge and re-encrypt routes that have the haproxy.router.openshift.io/hsts_header
annotation.
Prerequisites
- You are logged in to the cluster with a user with administrator privileges for the project.
-
You installed the OpenShift CLI (
oc
).
Procedure
To enable HSTS on a route, add the
haproxy.router.openshift.io/hsts_header
value to the edge-terminated or re-encrypt route. You can use theoc annotate
tool to do this by running the following command:$ oc annotate route <route_name> -n <namespace> --overwrite=true "haproxy.router.openshift.io/hsts_header"="max-age=31536000;\ 1 includeSubDomains;preload"
- 1
- In this example, the maximum age is set to
31536000
ms, which is approximately 8.5 hours.
NoteIn this example, the equal sign (
=
) is in quotes. This is required to properly execute the annotate command.Example route configured with an annotation
apiVersion: route.openshift.io/v1 kind: Route metadata: annotations: haproxy.router.openshift.io/hsts_header: max-age=31536000;includeSubDomains;preload 1 2 3 ... spec: host: def.abc.com tls: termination: "reencrypt" ... wildcardPolicy: "Subdomain"
- 1
- Required.
max-age
measures the length of time, in seconds, that the HSTS policy is in effect. If set to0
, it negates the policy. - 2
- Optional. When included,
includeSubDomains
tells the client that all subdomains of the host must have the same HSTS policy as the host. - 3
- Optional. When
max-age
is greater than 0, you can addpreload
inhaproxy.router.openshift.io/hsts_header
to allow external services to include this site in their HSTS preload lists. For example, sites such as Google can construct a list of sites that havepreload
set. Browsers can then use these lists to determine which sites they can communicate with over HTTPS, even before they have interacted with the site. Withoutpreload
set, browsers must have interacted with the site over HTTPS, at least once, to get the header.
10.1.3.2. Disabling HTTP Strict Transport Security per-route
To disable HTTP strict transport security (HSTS) per-route, you can set the max-age
value in the route annotation to 0
.
Prerequisites
- You are logged in to the cluster with a user with administrator privileges for the project.
-
You installed the OpenShift CLI (
oc
).
Procedure
To disable HSTS, set the
max-age
value in the route annotation to0
, by entering the following command:$ oc annotate route <route_name> -n <namespace> --overwrite=true "haproxy.router.openshift.io/hsts_header"="max-age=0"
TipYou can alternatively apply the following YAML to create the config map:
Example of disabling HSTS per-route
metadata: annotations: haproxy.router.openshift.io/hsts_header: max-age=0
To disable HSTS for every route in a namespace, enter the following command:
$ oc annotate route --all -n <namespace> --overwrite=true "haproxy.router.openshift.io/hsts_header"="max-age=0"
Verification
To query the annotation for all routes, enter the following command:
$ oc get route --all-namespaces -o go-template='{{range .items}}{{if .metadata.annotations}}{{$a := index .metadata.annotations "haproxy.router.openshift.io/hsts_header"}}{{$n := .metadata.name}}{{with $a}}Name: {{$n}} HSTS: {{$a}}{{"\n"}}{{else}}{{""}}{{end}}{{end}}{{end}}'
Example output
Name: routename HSTS: max-age=0
10.1.4. Using cookies to keep route statefulness
OpenShift Dedicated provides sticky sessions, which enables stateful application traffic by ensuring all traffic hits the same endpoint. However, if the endpoint pod terminates, whether through restart, scaling, or a change in configuration, this statefulness can disappear.
OpenShift Dedicated can use cookies to configure session persistence. The ingress controller selects an endpoint to handle any user requests, and creates a cookie for the session. The cookie is passed back in the response to the request and the user sends the cookie back with the next request in the session. The cookie tells the ingress controller which endpoint is handling the session, ensuring that client requests use the cookie so that they are routed to the same pod.
Cookies cannot be set on passthrough routes, because the HTTP traffic cannot be seen. Instead, a number is calculated based on the source IP address, which determines the backend.
If backends change, the traffic can be directed to the wrong server, making it less sticky. If you are using a load balancer, which hides source IP, the same number is set for all connections and traffic is sent to the same pod.
10.1.4.1. Annotating a route with a cookie
You can set a cookie name to overwrite the default, auto-generated one for the route. This allows the application receiving route traffic to know the cookie name. Deleting the cookie can force the next request to re-choose an endpoint. The result is that if a server is overloaded, that server tries to remove the requests from the client and redistribute them.
Procedure
Annotate the route with the specified cookie name:
$ oc annotate route <route_name> router.openshift.io/cookie_name="<cookie_name>"
where:
<route_name>
- Specifies the name of the route.
<cookie_name>
- Specifies the name for the cookie.
For example, to annotate the route
my_route
with the cookie namemy_cookie
:$ oc annotate route my_route router.openshift.io/cookie_name="my_cookie"
Capture the route hostname in a variable:
$ ROUTE_NAME=$(oc get route <route_name> -o jsonpath='{.spec.host}')
where:
<route_name>
- Specifies the name of the route.
Save the cookie, and then access the route:
$ curl $ROUTE_NAME -k -c /tmp/cookie_jar
Use the cookie saved by the previous command when connecting to the route:
$ curl $ROUTE_NAME -k -b /tmp/cookie_jar
10.1.5. Path-based routes
Path-based routes specify a path component that can be compared against a URL, which requires that the traffic for the route be HTTP based. Thus, multiple routes can be served using the same hostname, each with a different path. Routers should match routes based on the most specific path to the least.
The following table shows example routes and their accessibility:
Route | When Compared to | Accessible |
---|---|---|
www.example.com/test | www.example.com/test | Yes |
www.example.com | No | |
www.example.com/test and www.example.com | www.example.com/test | Yes |
www.example.com | Yes | |
www.example.com | www.example.com/text | Yes (Matched by the host, not the route) |
www.example.com | Yes |
An unsecured route with a path
apiVersion: route.openshift.io/v1
kind: Route
metadata:
name: route-unsecured
spec:
host: www.example.com
path: "/test" 1
to:
kind: Service
name: service-name
- 1
- The path is the only added attribute for a path-based route.
Path-based routing is not available when using passthrough TLS, as the router does not terminate TLS in that case and cannot read the contents of the request.
10.1.6. HTTP header configuration
OpenShift Dedicated provides different methods for working with HTTP headers. When setting or deleting headers, you can use specific fields in the Ingress Controller or an individual route to modify request and response headers. You can also set certain headers by using route annotations. The various ways of configuring headers can present challenges when working together.
You can only set or delete headers within an IngressController
or Route
CR, you cannot append them. If an HTTP header is set with a value, that value must be complete and not require appending in the future. In situations where it makes sense to append a header, such as the X-Forwarded-For header, use the spec.httpHeaders.forwardedHeaderPolicy
field, instead of spec.httpHeaders.actions
.
10.1.6.1. Order of precedence
When the same HTTP header is modified both in the Ingress Controller and in a route, HAProxy prioritizes the actions in certain ways depending on whether it is a request or response header.
- For HTTP response headers, actions specified in the Ingress Controller are executed after the actions specified in a route. This means that the actions specified in the Ingress Controller take precedence.
- For HTTP request headers, actions specified in a route are executed after the actions specified in the Ingress Controller. This means that the actions specified in the route take precedence.
For example, a cluster administrator sets the X-Frame-Options response header with the value DENY
in the Ingress Controller using the following configuration:
Example IngressController
spec
apiVersion: operator.openshift.io/v1 kind: IngressController # ... spec: httpHeaders: actions: response: - name: X-Frame-Options action: type: Set set: value: DENY
A route owner sets the same response header that the cluster administrator set in the Ingress Controller, but with the value SAMEORIGIN
using the following configuration:
Example Route
spec
apiVersion: route.openshift.io/v1 kind: Route # ... spec: httpHeaders: actions: response: - name: X-Frame-Options action: type: Set set: value: SAMEORIGIN
When both the IngressController
spec and Route
spec are configuring the X-Frame-Options response header, then the value set for this header at the global level in the Ingress Controller takes precedence, even if a specific route allows frames. For a request header, the Route
spec value overrides the IngressController
spec value.
This prioritization occurs because the haproxy.config
file uses the following logic, where the Ingress Controller is considered the front end and individual routes are considered the back end. The header value DENY
applied to the front end configurations overrides the same header with the value SAMEORIGIN
that is set in the back end:
frontend public http-response set-header X-Frame-Options 'DENY' frontend fe_sni http-response set-header X-Frame-Options 'DENY' frontend fe_no_sni http-response set-header X-Frame-Options 'DENY' backend be_secure:openshift-monitoring:alertmanager-main http-response set-header X-Frame-Options 'SAMEORIGIN'
Additionally, any actions defined in either the Ingress Controller or a route override values set using route annotations.
10.1.6.2. Special case headers
The following headers are either prevented entirely from being set or deleted, or allowed under specific circumstances:
Header name | Configurable using IngressController spec | Configurable using Route spec | Reason for disallowment | Configurable using another method |
---|---|---|---|---|
| No | No |
The | No |
| No | Yes |
When the | No |
| No | No |
The |
Yes: the |
| No | No | The cookies that HAProxy sets are used for session tracking to map client connections to particular back-end servers. Allowing these headers to be set could interfere with HAProxy’s session affinity and restrict HAProxy’s ownership of a cookie. | Yes:
|
10.1.7. Setting or deleting HTTP request and response headers in a route
You can set or delete certain HTTP request and response headers for compliance purposes or other reasons. You can set or delete these headers either for all routes served by an Ingress Controller or for specific routes.
For example, you might want to enable a web application to serve content in alternate locations for specific routes if that content is written in multiple languages, even if there is a default global location specified by the Ingress Controller serving the routes.
The following procedure creates a route that sets the Content-Location HTTP request header so that the URL associated with the application, https://app.example.com
, directs to the location https://app.example.com/lang/en-us
. Directing application traffic to this location means that anyone using that specific route is accessing web content written in American English.
Prerequisites
-
You have installed the OpenShift CLI (
oc
). - You are logged into an OpenShift Dedicated cluster as a project administrator.
- You have a web application that exposes a port and an HTTP or TLS endpoint listening for traffic on the port.
Procedure
Create a route definition and save it in a file called
app-example-route.yaml
:YAML definition of the created route with HTTP header directives
apiVersion: route.openshift.io/v1 kind: Route # ... spec: host: app.example.com tls: termination: edge to: kind: Service name: app-example httpHeaders: actions: 1 response: 2 - name: Content-Location 3 action: type: Set 4 set: value: /lang/en-us 5
- 1
- The list of actions you want to perform on the HTTP headers.
- 2
- The type of header you want to change. In this case, a response header.
- 3
- The name of the header you want to change. For a list of available headers you can set or delete, see HTTP header configuration.
- 4
- The type of action being taken on the header. This field can have the value
Set
orDelete
. - 5
- When setting HTTP headers, you must provide a
value
. The value can be a string from a list of available directives for that header, for exampleDENY
, or it can be a dynamic value that will be interpreted using HAProxy’s dynamic value syntax. In this case, the value is set to the relative location of the content.
Create a route to your existing web application using the newly created route definition:
$ oc -n app-example create -f app-example-route.yaml
For HTTP request headers, the actions specified in the route definitions are executed after any actions performed on HTTP request headers in the Ingress Controller. This means that any values set for those request headers in a route will take precedence over the ones set in the Ingress Controller. For more information on the processing order of HTTP headers, see HTTP header configuration.
10.1.8. Route-specific annotations
The Ingress Controller can set the default options for all the routes it exposes. An individual route can override some of these defaults by providing specific configurations in its annotations. Red Hat does not support adding a route annotation to an operator-managed route.
To create a whitelist with multiple source IPs or subnets, use a space-delimited list. Any other delimiter type causes the list to be ignored without a warning or error message.
Variable | Description | Environment variable used as default |
---|---|---|
|
Sets the load-balancing algorithm. Available options are |
|
|
Disables the use of cookies to track related connections. If set to | |
| Specifies an optional cookie to use for this route. The name must consist of any combination of upper and lower case letters, digits, "_", and "-". The default is the hashed internal key name for the route. | |
|
Sets the maximum number of connections that are allowed to a backing pod from a router. | |
|
Setting | |
|
Limits the number of concurrent TCP connections made through the same source IP address. It accepts a numeric value. | |
|
Limits the rate at which a client with the same source IP address can make HTTP requests. It accepts a numeric value. | |
|
Limits the rate at which a client with the same source IP address can make TCP connections. It accepts a numeric value. | |
| Sets a server-side timeout for the route. (TimeUnits) |
|
| This timeout applies to a tunnel connection, for example, WebSocket over cleartext, edge, reencrypt, or passthrough routes. With cleartext, edge, or reencrypt route types, this annotation is applied as a timeout tunnel with the existing timeout value. For the passthrough route types, the annotation takes precedence over any existing timeout value set. |
|
|
You can set either an IngressController or the ingress config . This annotation redeploys the router and configures the HA proxy to emit the haproxy |
|
| Sets the interval for the back-end health checks. (TimeUnits) |
|
| Sets an allowlist for the route. The allowlist is a space-separated list of IP addresses and CIDR ranges for the approved source addresses. Requests from IP addresses that are not in the allowlist are dropped.
The maximum number of IP addresses and CIDR ranges directly visible in the | |
| Sets a Strict-Transport-Security header for the edge terminated or re-encrypt route. | |
| Sets the rewrite path of the request on the backend. | |
| Sets a value to restrict cookies. The values are:
This value is applicable to re-encrypt and edge routes only. For more information, see the SameSite cookies documentation. | |
|
Sets the policy for handling the
|
|
If the number of IP addresses and CIDR ranges in an allowlist exceeds 61, they are written into a separate file that is then referenced from
haproxy.config
. This file is stored in thevar/lib/haproxy/router/whitelists
folder.NoteTo ensure that the addresses are written to the allowlist, check that the full list of CIDR ranges are listed in the Ingress Controller configuration file. The etcd object size limit restricts how large a route annotation can be. Because of this, it creates a threshold for the maximum number of IP addresses and CIDR ranges that you can include in an allowlist.
Environment variables cannot be edited.
Router timeout variables
TimeUnits
are represented by a number followed by the unit: us
*(microseconds), ms
(milliseconds, default), s
(seconds), m
(minutes), h
*(hours), d
(days).
The regular expression is: [1-9][0-9]*(us
\|ms
\|s
\|m
\|h
\|d
).
Variable | Default | Description |
---|---|---|
|
| Length of time between subsequent liveness checks on back ends. |
|
| Controls the TCP FIN timeout period for the client connecting to the route. If the FIN sent to close the connection does not answer within the given time, HAProxy closes the connection. This is harmless if set to a low value and uses fewer resources on the router. |
|
| Length of time that a client has to acknowledge or send data. |
|
| The maximum connection time. |
|
| Controls the TCP FIN timeout from the router to the pod backing the route. |
|
| Length of time that a server has to acknowledge or send data. |
|
| Length of time for TCP or WebSocket connections to remain open. This timeout period resets whenever HAProxy reloads. |
|
|
Set the maximum time to wait for a new HTTP request to appear. If this is set too low, it can cause problems with browsers and applications not expecting a small
Some effective timeout values can be the sum of certain variables, rather than the specific expected timeout. For example, |
|
| Length of time the transmission of an HTTP request can take. |
|
| Allows the minimum frequency for the router to reload and accept new changes. |
|
| Timeout for the gathering of HAProxy metrics. |
A route setting custom timeout
apiVersion: route.openshift.io/v1
kind: Route
metadata:
annotations:
haproxy.router.openshift.io/timeout: 5500ms 1
...
- 1
- Specifies the new timeout with HAProxy supported units (
us
,ms
,s
,m
,h
,d
). If the unit is not provided,ms
is the default.
Setting a server-side timeout value for passthrough routes too low can cause WebSocket connections to timeout frequently on that route.
A route that allows only one specific IP address
metadata: annotations: haproxy.router.openshift.io/ip_whitelist: 192.168.1.10
A route that allows several IP addresses
metadata: annotations: haproxy.router.openshift.io/ip_whitelist: 192.168.1.10 192.168.1.11 192.168.1.12
A route that allows an IP address CIDR network
metadata: annotations: haproxy.router.openshift.io/ip_whitelist: 192.168.1.0/24
A route that allows both IP an address and IP address CIDR networks
metadata: annotations: haproxy.router.openshift.io/ip_whitelist: 180.5.61.153 192.168.1.0/24 10.0.0.0/8
A route specifying a rewrite target
apiVersion: route.openshift.io/v1
kind: Route
metadata:
annotations:
haproxy.router.openshift.io/rewrite-target: / 1
...
- 1
- Sets
/
as rewrite path of the request on the backend.
Setting the haproxy.router.openshift.io/rewrite-target
annotation on a route specifies that the Ingress Controller should rewrite paths in HTTP requests using this route before forwarding the requests to the backend application. The part of the request path that matches the path specified in spec.path
is replaced with the rewrite target specified in the annotation.
The following table provides examples of the path rewriting behavior for various combinations of spec.path
, request path, and rewrite target.
Route.spec.path | Request path | Rewrite target | Forwarded request path |
---|---|---|---|
/foo | /foo | / | / |
/foo | /foo/ | / | / |
/foo | /foo/bar | / | /bar |
/foo | /foo/bar/ | / | /bar/ |
/foo | /foo | /bar | /bar |
/foo | /foo/ | /bar | /bar/ |
/foo | /foo/bar | /baz | /baz/bar |
/foo | /foo/bar/ | /baz | /baz/bar/ |
/foo/ | /foo | / | N/A (request path does not match route path) |
/foo/ | /foo/ | / | / |
/foo/ | /foo/bar | / | /bar |
Certain special characters in haproxy.router.openshift.io/rewrite-target
require special handling because they must be escaped properly. Refer to the following table to understand how these characters are handled.
For character | Use characters | Notes |
---|---|---|
# | \# | Avoid # because it terminates the rewrite expression |
% | % or %% | Avoid odd sequences such as %%% |
‘ | \’ | Avoid ‘ because it is ignored |
All other valid URL characters can be used without escaping.
10.1.9. Creating a route using the default certificate through an Ingress object
If you create an Ingress object without specifying any TLS configuration, OpenShift Dedicated generates an insecure route. To create an Ingress object that generates a secure, edge-terminated route using the default ingress certificate, you can specify an empty TLS configuration as follows.
Prerequisites
- You have a service that you want to expose.
-
You have access to the OpenShift CLI (
oc
).
Procedure
Create a YAML file for the Ingress object. In this example, the file is called
example-ingress.yaml
:YAML definition of an Ingress object
apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: frontend ... spec: rules: ... tls: - {} 1
- 1
- Use this exact syntax to specify TLS without specifying a custom certificate.
Create the Ingress object by running the following command:
$ oc create -f example-ingress.yaml
Verification
Verify that OpenShift Dedicated has created the expected route for the Ingress object by running the following command:
$ oc get routes -o yaml
Example output
apiVersion: v1 items: - apiVersion: route.openshift.io/v1 kind: Route metadata: name: frontend-j9sdd 1 ... spec: ... tls: 2 insecureEdgeTerminationPolicy: Redirect termination: edge 3 ...
10.1.10. Creating a route using the destination CA certificate in the Ingress annotation
The route.openshift.io/destination-ca-certificate-secret
annotation can be used on an Ingress object to define a route with a custom destination CA certificate.
Prerequisites
- You may have a certificate/key pair in PEM-encoded files, where the certificate is valid for the route host.
- You may have a separate CA certificate in a PEM-encoded file that completes the certificate chain.
- You must have a separate destination CA certificate in a PEM-encoded file.
- You must have a service that you want to expose.
Procedure
Add the
route.openshift.io/destination-ca-certificate-secret
to the Ingress annotations:apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: frontend annotations: route.openshift.io/termination: "reencrypt" route.openshift.io/destination-ca-certificate-secret: secret-ca-cert 1 ...
- 1
- The annotation references a kubernetes secret.
The secret referenced in this annotation will be inserted into the generated route.
Example output
apiVersion: route.openshift.io/v1 kind: Route metadata: name: frontend annotations: route.openshift.io/termination: reencrypt route.openshift.io/destination-ca-certificate-secret: secret-ca-cert spec: ... tls: insecureEdgeTerminationPolicy: Redirect termination: reencrypt destinationCACertificate: | -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE----- ...
Additional resources
10.2. Secured routes
Secure routes provide the ability to use several types of TLS termination to serve certificates to the client. The following sections describe how to create re-encrypt, edge, and passthrough routes with custom certificates.
If you create routes in Microsoft Azure through public endpoints, the resource names are subject to restriction. You cannot create resources that use certain terms. For a list of terms that Azure restricts, see Resolve reserved resource name errors in the Azure documentation.
10.2.1. Creating a re-encrypt route with a custom certificate
You can configure a secure route using reencrypt TLS termination with a custom certificate by using the oc create route
command.
Prerequisites
- You must have a certificate/key pair in PEM-encoded files, where the certificate is valid for the route host.
- You may have a separate CA certificate in a PEM-encoded file that completes the certificate chain.
- You must have a separate destination CA certificate in a PEM-encoded file.
- You must have a service that you want to expose.
Password protected key files are not supported. To remove a passphrase from a key file, use the following command:
$ openssl rsa -in password_protected_tls.key -out tls.key
Procedure
This procedure creates a Route
resource with a custom certificate and reencrypt TLS termination. The following assumes that the certificate/key pair are in the tls.crt
and tls.key
files in the current working directory. You must also specify a destination CA certificate to enable the Ingress Controller to trust the service’s certificate. You may also specify a CA certificate if needed to complete the certificate chain. Substitute the actual path names for tls.crt
, tls.key
, cacert.crt
, and (optionally) ca.crt
. Substitute the name of the Service
resource that you want to expose for frontend
. Substitute the appropriate hostname for www.example.com
.
Create a secure
Route
resource using reencrypt TLS termination and a custom certificate:$ oc create route reencrypt --service=frontend --cert=tls.crt --key=tls.key --dest-ca-cert=destca.crt --ca-cert=ca.crt --hostname=www.example.com
If you examine the resulting
Route
resource, it should look similar to the following:YAML Definition of the Secure Route
apiVersion: route.openshift.io/v1 kind: Route metadata: name: frontend spec: host: www.example.com to: kind: Service name: frontend tls: termination: reencrypt key: |- -----BEGIN PRIVATE KEY----- [...] -----END PRIVATE KEY----- certificate: |- -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE----- caCertificate: |- -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE----- destinationCACertificate: |- -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE-----
See
oc create route reencrypt --help
for more options.
10.2.2. Creating an edge route with a custom certificate
You can configure a secure route using edge TLS termination with a custom certificate by using the oc create route
command. With an edge route, the Ingress Controller terminates TLS encryption before forwarding traffic to the destination pod. The route specifies the TLS certificate and key that the Ingress Controller uses for the route.
Prerequisites
- You must have a certificate/key pair in PEM-encoded files, where the certificate is valid for the route host.
- You may have a separate CA certificate in a PEM-encoded file that completes the certificate chain.
- You must have a service that you want to expose.
Password protected key files are not supported. To remove a passphrase from a key file, use the following command:
$ openssl rsa -in password_protected_tls.key -out tls.key
Procedure
This procedure creates a Route
resource with a custom certificate and edge TLS termination. The following assumes that the certificate/key pair are in the tls.crt
and tls.key
files in the current working directory. You may also specify a CA certificate if needed to complete the certificate chain. Substitute the actual path names for tls.crt
, tls.key
, and (optionally) ca.crt
. Substitute the name of the service that you want to expose for frontend
. Substitute the appropriate hostname for www.example.com
.
Create a secure
Route
resource using edge TLS termination and a custom certificate.$ oc create route edge --service=frontend --cert=tls.crt --key=tls.key --ca-cert=ca.crt --hostname=www.example.com
If you examine the resulting
Route
resource, it should look similar to the following:YAML Definition of the Secure Route
apiVersion: route.openshift.io/v1 kind: Route metadata: name: frontend spec: host: www.example.com to: kind: Service name: frontend tls: termination: edge key: |- -----BEGIN PRIVATE KEY----- [...] -----END PRIVATE KEY----- certificate: |- -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE----- caCertificate: |- -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE-----
See
oc create route edge --help
for more options.
10.2.3. Creating a passthrough route
You can configure a secure route using passthrough termination by using the oc create route
command. With passthrough termination, encrypted traffic is sent straight to the destination without the router providing TLS termination. Therefore no key or certificate is required on the route.
Prerequisites
- You must have a service that you want to expose.
Procedure
Create a
Route
resource:$ oc create route passthrough route-passthrough-secured --service=frontend --port=8080
If you examine the resulting
Route
resource, it should look similar to the following:A Secured Route Using Passthrough Termination
apiVersion: route.openshift.io/v1 kind: Route metadata: name: route-passthrough-secured 1 spec: host: www.example.com port: targetPort: 8080 tls: termination: passthrough 2 insecureEdgeTerminationPolicy: None 3 to: kind: Service name: frontend
The destination pod is responsible for serving certificates for the traffic at the endpoint. This is currently the only method that can support requiring client certificates, also known as two-way authentication.
10.2.4. Creating a route with externally managed certificate
Securing route with external certificates in TLS secrets is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.
For more information about the support scope of Red Hat Technology Preview features, see Technology Preview Features Support Scope.
You can configure OpenShift Dedicated routes with third-party certificate management solutions by using the .spec.tls.externalCertificate
field of the route API. You can reference externally managed TLS certificates via secrets, eliminating the need for manual certificate management. Using the externally managed certificate reduces errors ensuring a smoother rollout of certificate updates, enabling the OpenShift router to serve renewed certificates promptly.
This feature applies to both edge routes and re-encrypt routes.
Prerequisites
-
You must enable the
RouteExternalCertificate
feature gate. -
You must have the
create
andupdate
permissions on theroutes/custom-host
. -
You must have a secret containing a valid certificate/key pair in PEM-encoded format of type
kubernetes.io/tls
, which includes bothtls.key
andtls.crt
keys. - You must place the referenced secret in the same namespace as the route you want to secure.
Procedure
Create a
role
in the same namespace as the secret to allow the router service account read access by running the following command:$ oc create role secret-reader --verb=get,list,watch --resource=secrets --resource-name=<secret-name> \ 1 --namespace=<current-namespace> 2
Create a
rolebinding
in the same namespace as the secret and bind the router service account to the newly created role by running the following command:$ oc create rolebinding secret-reader-binding --role=secret-reader --serviceaccount=openshift-ingress:router --namespace=<current-namespace> 1
- 1
- Specify the namespace where both your secret and route reside.
Create a YAML file that defines the
route
and specifies the secret containing your certificate using the following example.YAML definition of the secure route
apiVersion: route.openshift.io/v1 kind: Route metadata: name: myedge namespace: test spec: host: myedge-test.apps.example.com tls: externalCertificate: name: <secret-name> 1 termination: edge [...] [...]
- 1
- Specify the actual name of your secret.
Create a
route
resource by running the following command:$ oc apply -f <route.yaml> 1
- 1
- Specify the generated YAML filename.
If the secret exists and has a certificate/key pair, the router will serve the generated certificate if all prerequisites are met.
If .spec.tls.externalCertificate
is not provided, the router will use default generated certificates.
You cannot provide the .spec.tls.certificate
field or the .spec.tls.key
field when using the .spec.tls.externalCertificate
field.
Additional resources
- For troubleshooting routes with externally managed certificates, check the OpenShift Dedicated router pod logs for errors, see Investigating pod issues.
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