Fix cluster join: k3s 1.34.0+k3s1 does not set master label.

[andrewd-zededa]

Description

New EVE-OS installs with k3s v1.34.2+k3s1 will not have nodes setting the node label node-role.kubernetes.io/master. Pillar/zedkube checks this before advertising cluster status via the /status web server endpoint.

Master label has been deprecated since 1.20
k3s stopped setting it in 1.34.0-rc1+k3s1 PR 12395

Fixes regression from: #5483

PR dependencies

None

How to test and validate this PR

• fresh usb install of EVE-OS HV=k "eve-k" which installs k3s 1.34.0 or higher (visible via kubectl get node)
• Create a cluster of nodes
• verify all nodes join the cluster via kubectl get node.

Changelog notes

None

PR Backports

• 16.0: I don't think its needed.
• 14.5-stable: No, as the feature is not available there.
• 13.4-stable: No, as the feature is not available there.

Checklist

• I've provided a proper description
• I've added the proper documentation
• I've tested my PR on amd64 device
• I've tested my PR on arm64 device
• I've written the test verification instructions
• I've set the proper labels to this PR

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• I've checked the boxes above, or I've provided a good reason why I didn't
  check them.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 26.49%. Comparing base (2281599) to head (732abe2).
⚠️ Report is 176 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5521      +/-   ##
==========================================
+ Coverage   19.52%   26.49%   +6.96%     
==========================================
  Files          19       19              
  Lines        3021     2314     -707     
==========================================
+ Hits          590      613      +23     
+ Misses       2310     1559     -751     
- Partials      121      142      +21     

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[naiming-zededa]

LGTM

[zedi-pramodh]

Does it break the upgrades from previous eve versions ? That is eve 16.0.0-lts will be running k3s 1.32 and in future if customer upgrades the eve version which contains 1.34 will there be any regression ?

[naiming-zededa]

Does it break the upgrades from previous eve versions ? That is eve 16.0.0-lts will be running k3s 1.32 and in future if customer upgrades the eve version which contains 1.34 will there be any regression ?

the patch has the 'OR' operation, it should handle both current and prior versions

[andrewd-zededa]

Does it break the upgrades from previous eve versions ? That is eve 16.0.0-lts will be running k3s 1.32 and in future if customer upgrades the eve version which contains 1.34 will there be any regression ?

The fix is implemented to be overly cautious and continue coverage of the old label master or the new label control-plane. The new label control-plane has been added by k3s since k3s repo commit 63f2211b314d5e2e8c7b7cef027ffe369b5955f5 from December of 2020.

[zedi-pramodh]

LGTM