[Improvement] kafka-addon support configure kerberos keytab file for each instance

[CharlesQQ]

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For now, we have a kafka cluster that needs to be containerized using kubeblocks; each kafka broker node is configured with a kerberos keytab file for security, and the keytab file is associated with the host name (instance name); we hope that the kafka addons can support the requirement to configure a keytab file for each instance

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The keytab file can be obtained through a remote interface (eg: http interface) containing a host name parameter. The keytab of each instance is different.

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The keytab should be stored in a secret and mounted to a fixed directory in the pod using volumemount; The mount path inside the pod is fixed, for example: /opt/.security/kafka.keytab

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[shanshanying]

@caiq1nyu I'm not sure about this part, can you help clarify?

[shanshanying]

Hi @CharlesQQ

after some discussion, we found one feasible way is:

Suppose you have generated a secret , containing keytabfile for all instances.

1. update ComponentDefintion to add an extra volumeMounts for keytabfile
   e.g.

# componentdefinition.yaml
volumeMounts:
  - name: keytabfile
    mountPath: /path/to/keytabfile

2. update start up script, parsing for each pod the crossponding keytable file mounted to '/path/to-keytabfile' and save it to /opt/.security/kafka.keytab

3. generate the secret for keytab files

4. create a cluster and specifying volumes info:

# cluster.yaml
    volumes:
      - name: keytabfile  # must match the name in step 1.
        secret:
          secretName: secret-generated-at-step-3

Hope this will help.