Backport of keyring: filter by region before checking version into release/1.4.x #14909
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Backport
This PR is auto-generated from #14901 to be assessed for backporting due to the inclusion of the label backport/1.4.x.
The below text is copied from the body of the original PR.
In #14821 we fixed a panic that can happen if a leadership election happens in the middle of an upgrade. That fix checks that all servers are at the minimum version before initializing the keyring (which blocks evaluation processing during trhe upgrade). But the check we implemented is over the serf membership, which includes servers in any federated regions, which don't necessarily have the same upgrade cycle.
Filter the version check by the leader's region.
Fixes #14896 but this fix makes me wonder if we have other lurking bugs in this version check.