Chapter 4. Configuring Service Registry on OpenShift

This chapter explains how to configure optional settings for Service Registry health checks on OpenShift:

4.1. Configuring Service Registry health checks on OpenShift

You can configure optional environment variables for liveness and readiness probes to monitor the health of the Service Registry server on OpenShift:

  • Liveness probes test if the application can make progress. If the application cannot make progress, OpenShift automatically restarts the failing Pod.
  • Readiness probes test if the application is ready to process requests. If the application is not ready, it can become overwhelmed by requests, and OpenShift stops sending requests for the time that the probe fails. If other Pods are OK, they continue to receive requests.
Important

The default values of the liveness and readiness environment variables are designed for most cases and should only be changed if required by your environment. Any changes to the defaults depend on your hardware, network, and amount of data stored. These values should be kept as low as possible to avoid unnecessary overhead.

Prerequisites

Procedure

  1. In the OpenShift Container Platform web console, log in using an account with cluster administrator privileges.
  2. Click Installed Operators > Red Hat Integration - Service Registry.
  3. On the ApicurioRegistry tab, click the Operator custom resource for your deployment, for example, example-apicurioregistry.
  4. In the main overview page, find the Deployment Name section and the corresponding DeploymentConfig name for your Service Registry deployment, for example, example-apicurioregistry.
  5. In the left navigation menu, click Workloads > Deployment Configs, and select your DeploymentConfig name.
  6. Click the Environment tab, and enter your environment variables in the Single values env section, for example:

    • NAME: LIVENESS_STATUS_RESET
    • VALUE: 350
  7. Click Save at the bottom.

    Alternatively, you can perform these steps using the OpenShift oc command. For more details, see the OpenShift CLI documentation.

4.2. Environment variables for Service Registry health checks

This section describes the available environment variables for Service Registry health checks on OpenShift. These include liveness and readiness probes to monitor the health of the Service Registry server on OpenShift. For an example procedure, see Section 4.1, “Configuring Service Registry health checks on OpenShift”.

Important

The following environment variables are provided for reference only. The default values are designed for most cases and should only be changed if required by your environment. Any changes to the defaults depend on your hardware, network, and amount of data stored. These values should be kept as low as possible to avoid unnecessary overhead.

Liveness environment variables

Table 4.1. Environment variables for Service Registry liveness probes

NameDescriptionTypeDefault

LIVENESS_ERROR_THRESHOLD

Number of liveness issues or errors that can occur before the liveness probe fails.

Integer

1

LIVENESS_COUNTER_RESET

Period in which the threshold number of errors must occur. For example, if this value is 60 and the threshold is 1, the check fails after two errors occur in 1 minute

Seconds

60

LIVENESS_STATUS_RESET

Number of seconds that must elapse without any more errors for the liveness probe to reset to OK status.

Seconds

300

LIVENESS_ERRORS_IGNORED

Comma-separated list of ignored liveness exceptions.

String

io.grpc.StatusRuntimeException,org.apache.kafka.streams.errors.InvalidStateStoreException

Note

Because OpenShift automatically restarts a Pod that fails a liveness check, the liveness settings, unlike readiness settings, do not directly affect behavior of Service Registry on OpenShift.

Readiness environment variables

Table 4.2. Environment variables for Service Registry readiness probes

NameDescriptionTypeDefault

READINESS_ERROR_THRESHOLD

Number of readiness issues or errors that can occur before the readiness probe fails.

Integer

1

READINESS_COUNTER_RESET

Period in which the threshold number of errors must occur. For example, if this value is 60 and the threshold is 1, the check fails after two errors occur in 1 minute.

Seconds

60

READINESS_STATUS_RESET

Number of seconds that must elapse without any more errors for the liveness probe to reset to OK status. In this case, this means how long the Pod stays not ready, until it returns to normal operation.

Seconds

300

READINESS_TIMEOUT

Readiness tracks the timeout of two operations:

  • How long it takes for storage requests to complete
  • How long it takes for HTTP REST API requests to return a response

If these operations take more time than the configured timeout, this is counted as a readiness issue or error. This value controls the timeouts for both operations.

Seconds

5