Backups with Cassandra 5 might fail

[rtib]

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This is more a discussion starter than an actual issue. First of all, I'd like to raise awareness for CASSANDRA-17470 due to which filesystem permissions of /var/lib/cassandra have changed.

I'm running medusa backup on schedule having a distinct - unprivileged - user set up. Upgrading my test cluster to Cassandra 5 rendered these backups failing, as the user running medusa cannot read the snapshots anymore.

The solution is as simple as add the medusa user to the cassandra group. I'm aware, that medusa packages doesn't manage any local user accounts, so there might no change necessary, however, I'd like to discuss opinions on if or how folks could be warned before masses run into the same issue.

┆Issue is synchronized with this Jira Story by Unito

[rzvoncek]

Hi @rtib !

Thanks a lot for bringing this to our attention. We'll probably have to add a check for this and fail early and clearly state what the issue is.

Otherwise it's quite a clash of two worlds. On one hand, you have folks configuring everything properly, who probably won't be caught off guard by this. On the other hand, you have the quick&easy users who install and go, and they might get puzzled.

We'll also need to think a bit about how to handle this.

[rtib]

A proper error message can be enough to face this issue.

Regarding your objection about experts and newbies: IMO, nobody was born as an expert, we all have had to learn it. However, I believe, that a quick and easy way to install and go for the most basic functionality, is lowering the threshold for new users and can support a steep learning curve.

In this case, it's a change which has been done to Cassandra but rendering a formerly working Medusa setup to fail. Even experts, assumed to be able to tackle the problem without huge effort, would appreciate a proper error message on that one.