How to set environment variables when creating a cluster?

[majian159]

How to set environment variables when creating a cluster?

[shanshanying]

Some envs are not known till creating time. In such cases, KubeBlocks provides a way to pass them through a special annotation: kubeblocks.io/extra-env

e.g. when create an oceanbase cluster, we can specify the zone number , tenant info as envs in the annotation ( key:value pairs, seprated by comma)

apiVersion: apps.kubeblocks.io/v1alpha1
kind: Cluster
metadata:
  annotations:
    kubeblocks.io/extra-env: '{"TENANT_NAME":"test","ZONE_COUNT":"1"}'
spec:
...

And these envs wlll be saved in a configmap named after '$(KB_CLUSTER_COMP)_env'. and PODs provisioined will refer to it in envFrom api.

[weicao]

How to set environment variables when creating a cluster?

Which kinds of environment variables do you want to set? Could you take an example?

[majian159]

How to set environment variables when creating a cluster?

Which kinds of environment variables do you want to set? Could you take an example?

I need to configure the ELASTICSEARCH_HEAP_SIZE environment variable for the Elasticsearch cluster.

[majian159]

It looks like extra-env is not working for me.

apiVersion: apps.kubeblocks.io/v1alpha1
kind: Cluster
metadata:
  annotations:
    kubeblocks.io/extra-env: '{"ELASTICSEARCH_HEAP_SIZE":"4Gi"}'
    kubeblocks.io/reconcile: "2024-06-06T02:23:49.822598568Z"
  labels:
    clusterdefinition.kubeblocks.io/name: elasticsearch
    clusterversion.kubeblocks.io/name: elasticsearch-8.8.2
  name: elasticsearch

I have no name!@elasticsearch-elasticsearch-0:/$ printenv | grep ELASTICSEARCH_HEAP_SIZE
ELASTICSEARCH_HEAP_SIZE=128m

[weicao]

Yes, because the environment variables passed from extra-env will be overridden by the values defined in the Pod's environment variables.

Here is a pr (#7587) that set user-provided env vars on all Pods of a Cluster.
It should be merged in KubeBlocks v0.8.4 and v0.9.

[shanshanying]

I checked the Addon and found the ENV is set in POD spec.

[shanshanying]

you may edit the clustedefinition first, to remove the env, and inject it during cluster annotation.