found invalid file member_id under data directory

[braghettos]

Bug report criteria

• This bug report is not security related, security issues should be disclosed privately via etcd maintainers.
• This is not a support request or question, support requests or questions should be raised in the etcd discussion forums.
• You have read the etcd bug reporting guidelines.
• Existing open issues along with etcd frequently asked questions have been checked and this is not a duplicate.

What happened?

Suddenly my etcd pod in Kubernetes was not running due to liveness and readiness probes failing. I've checked etcd pod logs and I found this message:

{"level":"warn","ts":"2025-03-03T10:05:48.524866Z","caller":"etcdmain/etcd.go:446","msg":"found invalid file under data directory","filename":"member_id","data-dir":"/bitnami/etcd/data"}

I have renamed that file to member_id.bak, I restarted the pod and everything now is working correctly. No new member_id file has been generated.

What is the role of this file? I was expecting it to be generated. Will everything work correctly without this file?

Thanks for any help!

What did you expect to happen?

The member_id file is regenerated or error messages in the pod log due to the absence of this file.

How can we reproduce it (as minimally and precisely as possible)?

I'm not able to reproduce the issue.

Anything else we need to know?

No response

Etcd version (please run commands below)

$ etcd --version
# paste output here
3.5.15

$ etcdctl version
# paste output here
3.5.15

Etcd configuration (command line flags or environment variables)

paste your configuration here

Etcd debug information (please run commands below, feel free to obfuscate the IP address or FQDN in the output)

$ etcdctl member list -w table
# paste output here

$ etcdctl --endpoints=<member list> endpoint status -w table
# paste output here

Relevant log output

[ivanvc]

Hi, @braghettos. Thanks for your request. We don't give support to the Bitnami etcd Helm chart. Have you reached out over there? I don't have a clear indication of what could have placed that file.

The database directory only has the WAL and snap directories.

[braghettos]

Hi @ivanvc, I thought it was an etcd upstream behavior, regardless of the Helm packaging. Thanks for clarifying that member_id is not a file written by etcd under /data.