[CI] SetSingleNodeAllocateStepTests testPerformActionSomeShardsOnlyOnNewNodesButNewNodesInvalidAttrs failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic-platform-support #6135 / oraclelinux-9_platform-support-unix
• elasticsearch-pull-request #54458 / part-2
• elasticsearch-periodic #6104 / openjdk21_checkpart2_java-fips-matrix

Reproduction Line:

./gradlew ":x-pack:plugin:core:test" --tests "org.elasticsearch.xpack.core.ilm.SetSingleNodeAllocateStepTests.testPerformActionSomeShardsOnlyOnNewNodesButNewNodesInvalidAttrs" -Dtests.seed=6DD3B21F36892442 -Dtests.locale=pt-GW -Dtests.timezone=Asia/Brunei -Druntime.java=23

Applicable branches:
main

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.AssertionError: unexpected

Issue Reasons:

• [main] 3 failures in test testPerformActionSomeShardsOnlyOnNewNodesButNewNodesInvalidAttrs (1.1% fail rate in 274 executions)

Note:
This issue was created using new test triage automation. Please report issues or feedback to es-delivery.

[elasticsearchmachine]

This has been muted on branch main

Mute Reasons:

• [main] 3 failures in test testPerformActionSomeShardsOnlyOnNewNodesButNewNodesInvalidAttrs (1.1% fail rate in 274 executions)

Build Scans:

• elasticsearch-periodic-platform-support #6135 / oraclelinux-9_platform-support-unix
• elasticsearch-pull-request #54458 / part-2
• elasticsearch-periodic #6104 / openjdk21_checkpart2_java-fips-matrix

[elasticsearchmachine]

Pinging @elastic/es-data-management (Team:Data Management)

[PeteGillinElastic]

I think this was fixed by #121266. At any rate, the repro I was using (with the mute removed)

./gradlew ":x-pack:plugin:core:test" --tests "org.elasticsearch.xpack.core.ilm.SetSingleNodeAllocateStepTests.testPerformActionSomeShardsOnlyOnNewNodesButNewNodesInvalidAttrs" -Dtests.seed=6DD3B21F36892442 -Dtests.locale=pt-GW -Dtests.timezone=Asia/Brunei -Druntime.java=23

passes at the commit from that PR (c288684fdbf85fb032510967bb2a4b5f47885b40), and fails at its parent (68c8fa6b38e9242be010204cae5fe4250a22f217). (Thank you git bisect!) And it looks like it's at least in broadly the right area.