Chapter 6. Ingress Operator in OpenShift Container Platform
6.1. OpenShift Container Platform Ingress Operator
When you create your OpenShift Container Platform 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 Container Platform 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. You can use the Ingress Operator to route traffic by specifying OpenShift Container Platform Route
and Kubernetes Ingress
resources. Configurations within the Ingress Controller, such as the ability to define endpointPublishingStrategy
type and internal load balancing, provide ways to publish Ingress Controller endpoints.
6.2. 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.
6.3. Ingress Controller configuration parameters
The ingresscontrollers.operator.openshift.io
resource offers the following configuration parameters.
Parameter | Description |
---|---|
|
The
If empty, the default value is |
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If not set, the default value is based on
For most platforms, 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 Container Platform built-in OAuth server. |
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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 |
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|
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 |
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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 |
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The
|
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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 |
All parameters are optional.
6.3.1. 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.
6.3.1.1. Understanding TLS security profiles
You can use a TLS (Transport Layer Security) security profile to define which TLS ciphers are required by various OpenShift Container Platform components. The OpenShift Container Platform 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.
6.3.1.2. 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 ...
6.3.1.3. 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$"
6.4. View the default Ingress Controller
The Ingress Operator is a core feature of OpenShift Container Platform and is enabled out of the box.
Every new OpenShift Container Platform 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
6.5. 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
6.6. 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>
6.7. 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>
6.8. Configuring the Ingress Controller
6.8.1. 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.
6.8.2. 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 Container Platform, 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
6.8.3. 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.
6.8.4. 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 Container Platform, 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.endpoint
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.
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
6.8.5. 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.
6.8.6. Ingress Controller sharding
As the primary mechanism for traffic to enter the cluster, the demands on the Ingress Controller, or router, can be significant. As a cluster administrator, you can shard the routes to:
- Balance Ingress Controllers, or routers, with several routes to speed up responses to changes.
- Allocate certain routes to have different reliability guarantees than other routes.
- Allow certain Ingress Controllers to have different policies defined.
- Allow only specific routes to use additional features.
- Expose different routes on different addresses so that internal and external users can see different routes, for example.
Ingress Controller can use either route labels or namespace labels as a sharding method.
6.8.6.1. Configuring Ingress Controller sharding by using route labels
Ingress Controller sharding by using route labels means that the Ingress Controller serves any route in any namespace that is selected by the route selector.
Ingress Controller sharding is useful when balancing incoming traffic load among a set of Ingress Controllers and when isolating traffic to a specific Ingress Controller. For example, company A goes to one Ingress Controller and company B to another.
Procedure
Edit the
router-internal.yaml
file:# cat router-internal.yaml apiVersion: v1 items: - apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: sharded namespace: openshift-ingress-operator spec: domain: <apps-sharded.basedomain.example.net> 1 nodePlacement: nodeSelector: matchLabels: node-role.kubernetes.io/worker: "" routeSelector: matchLabels: type: sharded status: {} kind: List metadata: resourceVersion: "" selfLink: ""
- 1
- Specify a domain to be used by the Ingress Controller. This domain must be different from the default Ingress Controller domain.
Apply the Ingress Controller
router-internal.yaml
file:# oc apply -f router-internal.yaml
The Ingress Controller selects routes in any namespace that have the label
type: sharded
.Create a new route using the domain configured in the
router-internal.yaml
:$ oc expose svc <service-name> --hostname <route-name>.apps-sharded.basedomain.example.net
6.8.6.2. Configuring Ingress Controller sharding by using namespace labels
Ingress Controller sharding by using namespace labels means that the Ingress Controller serves any route in any namespace that is selected by the namespace selector.
Ingress Controller sharding is useful when balancing incoming traffic load among a set of Ingress Controllers and when isolating traffic to a specific Ingress Controller. For example, company A goes to one Ingress Controller and company B to another.
If you deploy the Keepalived Ingress VIP, do not deploy a non-default Ingress Controller with value HostNetwork
for the endpointPublishingStrategy
parameter. Doing so might cause issues. Use value NodePort
instead of HostNetwork
for endpointPublishingStrategy
.
Procedure
Edit the
router-internal.yaml
file:# cat router-internal.yaml
Example output
apiVersion: v1 items: - apiVersion: operator.openshift.io/v1 kind: IngressController metadata: name: sharded namespace: openshift-ingress-operator spec: domain: <apps-sharded.basedomain.example.net> 1 nodePlacement: nodeSelector: matchLabels: node-role.kubernetes.io/worker: "" namespaceSelector: matchLabels: type: sharded status: {} kind: List metadata: resourceVersion: "" selfLink: ""
- 1
- Specify a domain to be used by the Ingress Controller. This domain must be different from the default Ingress Controller domain.
Apply the Ingress Controller
router-internal.yaml
file:# oc apply -f router-internal.yaml
The Ingress Controller selects routes in any namespace that is selected by the namespace selector that have the label
type: sharded
.Create a new route using the domain configured in the
router-internal.yaml
:$ oc expose svc <service-name> --hostname <route-name>.apps-sharded.basedomain.example.net
6.8.7. 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 your cloud provider is Microsoft Azure, you must have at least one public load balancer that points to your nodes. If you do not, all of your nodes will lose egress connectivity to the internet.
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 6.1. Diagram of LoadBalancer
The preceding graphic shows the following concepts pertaining to OpenShift Container Platform 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
6.8.8. Configuring global access for an Ingress Controller on GCP
An Ingress Controller created on GCP with an internal load balancer generates an internal IP address for the service. A cluster administrator can specify the global access option, which enables clients in any region within the same VPC network and compute region as the load balancer, to reach the workloads running on your cluster.
For more information, see the GCP documentation for global access.
Prerequisites
- You deployed an OpenShift Container Platform cluster on GCP infrastructure.
- You configured an Ingress Controller to use an internal load balancer.
-
You installed the OpenShift CLI (
oc
).
Procedure
Configure the Ingress Controller resource to allow global access.
NoteYou can also create an Ingress Controller and specify the global access option.
Configure the Ingress Controller resource:
$ oc -n openshift-ingress-operator edit ingresscontroller/default
Edit the YAML file:
Sample
clientAccess
configuration toGlobal
spec: endpointPublishingStrategy: loadBalancer: providerParameters: gcp: clientAccess: Global 1 type: GCP scope: Internal type: LoadBalancerService
- 1
- Set
gcp.clientAccess
toGlobal
.
- Save the file to apply the changes.
Run the following command to verify that the service allows global access:
$ oc -n openshift-ingress edit svc/router-default -o yaml
The output shows that global access is enabled for GCP with the annotation,
networking.gke.io/internal-load-balancer-allow-global-access
.
6.8.9. 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 your cloud provider is Microsoft Azure, you must have at least one public load balancer that points to your nodes. If you do not, all of your nodes will lose egress connectivity to the internet.
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
6.8.10. 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
6.8.11. 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
6.8.12. 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.
6.8.13. 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.
Using WebSockets with a re-encrypt route and with HTTP/2 enabled on an Ingress Controller requires WebSocket support over HTTP/2. WebSockets over HTTP/2 is a feature of HAProxy 2.4, which is unsupported in OpenShift Container Platform at this time.
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"
6.8.14. Configuring the PROXY protocol for an Ingress Controller
A cluster administrator can configure the PROXY protocol when an Ingress Controller uses either the HostNetwork
or NodePortService
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.
This feature is not supported in cloud deployments. This restriction is because when OpenShift Container Platform runs in a cloud platform, and an IngressController 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 Container Platform and the external load balancer to either use the PROXY protocol or to use TCP.
The PROXY protocol is unsupported for the default Ingress Controller with installer-provisioned clusters on non-cloud platforms that use a Keepalived Ingress VIP.
Prerequisites
- You created an Ingress Controller.
Procedure
Edit the Ingress Controller resource:
$ oc -n openshift-ingress-operator edit ingresscontroller/default
Set the PROXY configuration:
If your Ingress Controller uses the hostNetwork endpoint publishing strategy type, set the
spec.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 the
spec.endpointPublishingStrategy.nodePort.protocol
subfield toPROXY
:Sample
nodePort
configuration toPROXY
spec: endpointPublishingStrategy: nodePort: protocol: PROXY type: NodePortService
6.8.15. 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 Container Platform 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 Container Platform 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
6.8.16. Converting HTTP header case
HAProxy 2.2 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.
Because OpenShift Container Platform 4.10 includes HAProxy 2.2, make sure to add the necessary configuration by using spec.httpHeaders.headerNameCaseAdjustments
before upgrading.
Prerequisites
-
You have installed the OpenShift CLI (
oc
). -
You have access to the cluster as a user with the
cluster-admin
role.
Procedure
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.
Specify an HTTP header to be capitalized by entering the
oc patch
command.Enter the
oc patch
command to change the HTTPhost
header toHost
:$ oc -n openshift-ingress-operator patch ingresscontrollers/default --type=merge --patch='{"spec":{"httpHeaders":{"headerNameCaseAdjustments":["Host"]}}}'
Annotate the route of the application:
$ oc annotate routes/my-application haproxy.router.openshift.io/h1-adjust-case=true
The Ingress Controller then adjusts the
host
request header as specified.
Specify adjustments using the
HeaderNameCaseAdjustments
field by configuring the Ingress Controller YAML file.The following example Ingress Controller YAML 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 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.
6.8.17. 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" ...
6.8.18. 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 6.1. 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
6.8.19. 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 Container Platform 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 Container Platform 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 Container Platform 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