Chapter 6. Configuring routes
You can configure routes for MicroShift for clusters.
6.1. 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-microshift
application as an example.
Prerequisites
-
You installed the OpenShift CLI (
oc
). - You have access to your MicroShift cluster.
- You have a web application that exposes a port and a TCP endpoint listening for traffic on the port.
Procedure
Create a service called
hello-microshift
by running the following command:$ oc expose pod hello-microshift -n $namespace
Create an unsecured route to the
hello-microshift
application by running the following command:$ oc expose svc/hello-microshift --hostname=microshift.com $namespace
Verification
Verify that the
route
resource was created by running the following command:$ oc get routes -o yaml <name of resource> -n $namespace 1
- 1
- In this example, the route is named
hello-microshift
and the namespace is namedhello-microshift
.
Sample YAML definition of the created unsecured route:
apiVersion: route.openshift.io/v1 kind: Route metadata: name: hello-microshift namespace: hello-microshift spec: host: microshift.com 1 port: targetPort: 8080 2 to: kind: Service name: hello-microshift
6.2. HTTP Strict Transport Security
HTTP Strict Transport Security (HSTS) policy is a security enhancement, which signals to the browser client that only HTTPS traffic is allowed on the route host. HSTS also optimizes web traffic by signaling HTTPS transport is required, without using HTTP redirects. HSTS is useful for speeding up interactions with websites.
When HSTS policy is enforced, HSTS adds a Strict Transport Security header to HTTP and HTTPS responses from the site. You can use the insecureEdgeTerminationPolicy
value in a route to redirect HTTP to HTTPS. When HSTS is enforced, the client changes all requests from the HTTP URL to HTTPS before the request is sent, eliminating the need for a redirect.
Cluster administrators can configure HSTS to do the following:
- Enable HSTS per-route
- Disable HSTS per-route
- Enforce HSTS per-domain, for a set of domains, or use namespace labels in combination with domains
HSTS works only with secure routes, either edge-terminated or re-encrypt. The configuration is ineffective on HTTP or passthrough routes.
6.3. Enabling HTTP Strict Transport Security per-route
HTTP strict transport security (HSTS) is implemented in the HAProxy template and applied to edge and re-encrypt routes that have the haproxy.router.openshift.io/hsts_header
annotation.
Prerequisites
- You have root access to the cluster.
-
You installed the OpenShift CLI (
oc
).
Procedure
To enable HSTS on a route, add the
haproxy.router.openshift.io/hsts_header
value to the edge-terminated or re-encrypt route. You can use theoc annotate
tool to do this by running the following command:$ 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.
6.3.1. 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 have root access to the cluster.
-
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: {{$a}}{{"\n"}}{{else}}{{""}}{{end}}{{end}}{{end}}'
Example output
Name: routename HSTS: max-age=0
6.3.2. Enforcing HTTP Strict Transport Security per-domain
You can configure a route with a compliant HSTS policy annotation. To handle upgraded clusters with non-compliant HSTS routes, you can update the manifests at the source and apply the updates.
You cannot use oc expose route
or oc create route
commands to add a route in a domain that enforces HSTS because the API for these commands does not accept annotations.
HSTS cannot be applied to insecure, or non-TLS, routes.
Prerequisites
- You have root access to the cluster.
-
You installed the OpenShift CLI (
oc
).
Procedure
Apply HSTS to all routes in the cluster by running the following
oc annotate command
:$ oc annotate route --all --all-namespaces --overwrite=true "haproxy.router.openshift.io/hsts_header"="max-age=31536000;preload;includeSubDomains"
Apply HSTS to all routes in a particular namespace by running the following
oc annotate command
:$ oc annotate route --all -n <my_namespace> --overwrite=true "haproxy.router.openshift.io/hsts_header"="max-age=31536000;preload;includeSubDomains" 1
- 1
- Replace _<my_namespace> with the namespace you want to use.
Verification
Review the HSTS annotations on all routes by running 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: {{$a}}{{"\n"}}{{else}}{{""}}{{end}}{{end}}{{end}}'
Example output
Name: <_routename_> HSTS: max-age=31536000;preload;includeSubDomains
6.4. Throughput issue troubleshooting methods
Sometimes applications deployed by using MicroShift can cause network throughput issues, such as unusually high latency between specific services.
If pod logs do not reveal any cause of the problem, use the following methods to analyze performance issues:
Use a packet analyzer, such as
ping
ortcpdump
to analyze traffic between a pod and its node.For example, run the
tcpdump
tool on each pod while reproducing the behavior that led to the issue. Review the captures on both sides to compare send and receive timestamps to analyze the latency of traffic to and from a pod. Latency can occur in MicroShift if a node interface is overloaded with traffic from other pods, storage devices, or the data plane.$ tcpdump -s 0 -i any -w /tmp/dump.pcap host <podip 1> && host <podip 2> 1
- 1
podip
is the IP address for the pod. Run theoc get pod <pod_name> -o wide
command to get the IP address of a pod.
The
tcpdump
command generates a file at/tmp/dump.pcap
containing all traffic between these two pods. You can run the analyzer shortly before the issue is reproduced and stop the analyzer shortly after the issue is finished reproducing to minimize the size of the file. You can also run a packet analyzer between the nodes (eliminating the SDN from the equation) with:$ tcpdump -s 0 -i any -w /tmp/dump.pcap port 4789
-
Use a bandwidth measuring tool, such as
iperf
, to measure streaming throughput and UDP throughput. Locate any bottlenecks by running the tool from the pods first, and then running it from the nodes.
6.5. Using cookies to keep route statefulness
MicroShift 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.
MicroShift 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.
6.5.1. 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
6.6. 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.
6.7. HTTP header configuration
When setting or deleting headers, you can use 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 a Route
CR. You cannot append headers. 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
.
Example Route
spec
apiVersion: route.openshift.io/v1 kind: Route # ... spec: httpHeaders: actions: response: - name: X-Frame-Options action: type: Set set: value: SAMEORIGIN
Any actions defined in a route override values set using route annotations.
6.7.1. Special case headers
The following headers are either prevented entirely from being set or deleted, or allowed under specific circumstances:
Header name | Configurable using Route spec | Reason for disallowment | Configurable using another method |
---|---|---|---|
| No |
The | No |
| Yes |
When the | No |
| No |
The |
Yes: the |
| 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:
* the |
6.8. 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 MicroShift 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.
6.9. Creating a route through an Ingress object
Some ecosystem components have an integration with Ingress resources but not with route resources. To cover this case, MicroShift automatically creates managed route objects when an Ingress object is created. These route objects are deleted when the corresponding Ingress objects are deleted.
Procedure
Define an Ingress object in the MicroShift console or by entering the
oc create
command:YAML Definition of an Ingress
apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: frontend annotations: route.openshift.io/termination: "reencrypt" 1 route.openshift.io/destination-ca-certificate-secret: secret-ca-cert 2 spec: rules: - host: www.example.com 3 http: paths: - backend: service: name: frontend port: number: 443 path: / pathType: Prefix tls: - hosts: - www.example.com secretName: example-com-tls-certificate
- 1
- The
route.openshift.io/termination
annotation can be used to configure thespec.tls.termination
field of theRoute
asIngress
has no field for this. The accepted values areedge
,passthrough
andreencrypt
. All other values are silently ignored. When the annotation value is unset,edge
is the default route. The TLS certificate details must be defined in the template file to implement the default edge route. - 3
- When working with an
Ingress
object, you must specify an explicit hostname, unlike when working with routes. You can use the<host_name>.<cluster_ingress_domain>
syntax, for exampleapps.openshiftdemos.com
, to take advantage of the*.<cluster_ingress_domain>
wildcard DNS record and serving certificate for the cluster. Otherwise, you must ensure that there is a DNS record for the chosen hostname.If you specify the
passthrough
value in theroute.openshift.io/termination
annotation, setpath
to''
andpathType
toImplementationSpecific
in the spec:spec: rules: - host: www.example.com http: paths: - path: '' pathType: ImplementationSpecific backend: service: name: frontend port: number: 443
$ oc apply -f ingress.yaml
- 2
- The
route.openshift.io/destination-ca-certificate-secret
can be used on an Ingress object to define a route with a custom destination certificate (CA). The annotation references a kubernetes secret,secret-ca-cert
that will be inserted into the generated route.-
To specify a route object with a destination CA from an ingress object, you must create a
kubernetes.io/tls
orOpaque
type secret with a certificate in PEM-encoded format in thedata.tls.crt
specifier of the secret.
-
To specify a route object with a destination CA from an ingress object, you must create a
List your routes:
$ oc get routes
The result includes an autogenerated route whose name starts with
frontend-
:NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD frontend-gnztq www.example.com frontend 443 reencrypt/Redirect None
If you inspect this route, it looks this:
YAML Definition of an autogenerated route
apiVersion: route.openshift.io/v1 kind: Route metadata: name: frontend-gnztq ownerReferences: - apiVersion: networking.k8s.io/v1 controller: true kind: Ingress name: frontend uid: 4e6c59cc-704d-4f44-b390-617d879033b6 spec: host: www.example.com path: / port: targetPort: https tls: certificate: | -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE----- insecureEdgeTerminationPolicy: Redirect key: | -----BEGIN RSA PRIVATE KEY----- [...] -----END RSA PRIVATE KEY----- termination: reencrypt destinationCACertificate: | -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE----- to: kind: Service name: frontend
6.10. Creating a route using the default certificate through an Ingress object
If you create an Ingress object without specifying any TLS configuration, MicroShift 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 MicroShift 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 ...
6.11. 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----- ...
6.12. Secured routes
Secure routes provide the ability to use several types of TLS termination to serve certificates to the client. The following links to the OpenShift Container Platform documentation describe how to create re-encrypt, edge, and passthrough routes with custom certificates.