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Chapter 9. Configuring Routes

9.1. Route configuration

9.1.1. 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

  1. 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

9.1.2. Enabling HTTP strict transport security

HTTP Strict Transport Security (HSTS) policy is a security enhancement, which ensures that only HTTPS traffic is allowed on the host. Any HTTP requests are dropped by default. This is useful for ensuring secure interactions with websites, or to offer a secure application for the user’s benefit.

When HSTS is enabled, HSTS adds a Strict Transport Security header to HTTPS responses from the site. You can use the insecureEdgeTerminationPolicy value in a route to redirect to send HTTP to HTTPS. However, when HSTS is enabled, the client changes all requests from the HTTP URL to HTTPS before the request is sent, eliminating the need for a redirect. This is not required to be supported by the client, and can be disabled by setting max-age=0.

Important

HSTS works only with secure routes (either edge terminated or re-encrypt). The configuration is ineffective on HTTP or passthrough routes.

Procedure

  • To enable HSTS on a route, add the haproxy.router.openshift.io/hsts_header value to the edge terminated or re-encrypt route:

    apiVersion: v1
    kind: Route
    metadata:
      annotations:
        haproxy.router.openshift.io/hsts_header: max-age=31536000;includeSubDomains;preload 1 2 3
    1
    max-age is the only required parameter. It measures the length of time, in seconds, that the HSTS policy is in effect. The client updates max-age whenever a response with a HSTS header is received from the host. When max-age times out, the client discards the policy.
    2
    includeSubDomains is optional. When included, it tells the client that all subdomains of the host are to be treated the same as the host.
    3
    preload is optional. When max-age is greater than 0, then including preload in haproxy.router.openshift.io/hsts_header allows external services to include this site in their HSTS preload lists. For example, sites such as Google can construct a list of sites that have preload set. Browsers can then use these lists to determine which sites they can communicate with over HTTPS, before they have interacted with the site. Without preload set, browsers must have interacted with the site over HTTPS to get the header.

9.1.3. Troubleshooting throughput issues

Sometimes applications deployed through OpenShift Container Platform can cause network throughput issues such as unusually high latency between specific services.

Use the following methods to analyze performance issues if Pod logs do not reveal any cause of the problem:

  • Use a packet analyzer, such as ping or tcpdump 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 OpenShift Container Platform 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 the oc get pod <pod_name> -o wide command to get the IP address of a Pod.

    tcpdump generates a file at /tmp/dump.pcap containing all traffic between these two Pods. Ideally, 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. Run the tool from the Pods first, then from the nodes, to locate any bottlenecks.

9.1.4. Using cookies to keep route statefulness

OpenShift Container Platform 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 Container Platform 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.

9.1.5. 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.

Table 9.1. Route annotations

VariableDescriptionEnvironment variable used as default

haproxy.router.openshift.io/balance

Sets the load-balancing algorithm. Available options are source, roundrobin, and leastconn.

ROUTER_TCP_BALANCE_SCHEME for passthrough routes. Otherwise, use ROUTER_LOAD_BALANCE_ALGORITHM.

haproxy.router.openshift.io/disable_cookies

Disables the use of cookies to track related connections. If set to true or TRUE, the balance algorithm is used to choose which back-end serves connections for each incoming HTTP request.

 

router.openshift.io/cookie_name

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.

 

haproxy.router.openshift.io/pod-concurrent-connections

Sets the maximum number of connections that are allowed to a backing pod from a router. Note: if there are multiple pods, each can have this many connections. But if you have multiple routers, there is no coordination among them, each may connect this many times. If not set, or set to 0, there is no limit.

 

haproxy.router.openshift.io/rate-limit-connections

Setting true or TRUE to enables rate limiting functionality.

 

haproxy.router.openshift.io/rate-limit-connections.concurrent-tcp

Limits the number of concurrent TCP connections shared by an IP address.

 

haproxy.router.openshift.io/rate-limit-connections.rate-http

Limits the rate at which an IP address can make HTTP requests.

 

haproxy.router.openshift.io/rate-limit-connections.rate-tcp

Limits the rate at which an IP address can make TCP connections.

 

haproxy.router.openshift.io/timeout

Sets a server-side timeout for the route. (TimeUnits)

ROUTER_DEFAULT_SERVER_TIMEOUT

router.openshift.io/haproxy.health.check.interval

Sets the interval for the back-end health checks. (TimeUnits)

ROUTER_BACKEND_CHECK_INTERVAL

haproxy.router.openshift.io/ip_whitelist

Sets a whitelist for the route.

 

haproxy.router.openshift.io/hsts_header

Sets a Strict-Transport-Security header for the edge terminated or re-encrypt route.

 
Note

Environment variables can not be edited.

A route setting custom timeout

apiVersion: 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.
Note

Setting a server-side timeout value for passthrough routes too low can cause WebSocket connections to timeout frequently on that route.

9.2. Secured routes

The following sections describe how to create re-encrypt and edge routes with custom certificates.

9.2.1. 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 resource that you want to expose.
Note

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 host name 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: 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.

9.2.2. 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 resource that you want to expose.
Note

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 resource that you want to expose for frontend. Substitute the appropriate host name 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: 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.