Just started a short while ago today...

**Build scan:**
https://gradle-enterprise.elastic.co/s/hlqbul7ecwrju/tests/:x-pack:qa:rolling-upgrade-multi-cluster:v8.12.0%23follower%23twoThirdsUpgradedTest/org.elasticsearch.upgrades.CcrRollingUpgradeIT/testAutoFollowing
**Reproduction line:**
```
./gradlew ':x-pack:qa:rolling-upgrade-multi-cluster:v8.12.0#follower#twoThirdsUpgradedTest' -Dtests.class="org.elasticsearch.upgrades.CcrRollingUpgradeIT" -Dtests.method="testAutoFollowing" -Dtests.seed=30CC5E7003991EBA -Dtests.bwc=true -Dtests.locale=ar-SD -Dtests.timezone=America/Havana -Druntime.java=21
```

**Applicable branches:**
main

**Reproduces locally?:**
Didn't try

**Failure history:**
https://gradle-enterprise.elastic.co/scans/tests?tests.container=org.elasticsearch.upgrades.CcrRollingUpgradeIT&tests.test=testAutoFollowing


**Failure excerpt:**
```
org.elasticsearch.client.ResponseException: method [POST], host [http://127.0.0.1:41851], URI [/copy-logs-20200101/_refresh], status line [HTTP/1.1 404 Not Found]
{"error":{"root_cause":[{"type":"index_not_found_exception","reason":"no such index [copy-logs-20200101]","resource.type":"index_or_alias","resource.id":"copy-logs-20200101","index_uuid":"_na_","index":"copy-logs-20200101"}],"type":"index_not_found_exception","reason":"no such index [copy-logs-20200101]","resource.type":"index_or_alias","resource.id":"copy-logs-20200101","index_uuid":"_na_","index":"copy-logs-20200101"},"status":404}

  at __randomizedtesting.SeedInfo.seed([30CC5E7003991EBA:9F2278700730B597]:0)
  at org.elasticsearch.client.RestClient.convertResponse(RestClient.java:347)
  at org.elasticsearch.client.RestClient.performRequest(RestClient.java:313)
  at org.elasticsearch.client.RestClient.performRequest(RestClient.java:288)
  at org.elasticsearch.upgrades.CcrRollingUpgradeIT.assertTotalHitCount(CcrRollingUpgradeIT.java:365)
  at org.elasticsearch.upgrades.CcrRollingUpgradeIT.lambda$testAutoFollowing$6(CcrRollingUpgradeIT.java:162)
  at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:1203)
  at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:1188)
  at org.elasticsearch.upgrades.CcrRollingUpgradeIT.testAutoFollowing(CcrRollingUpgradeIT.java:160)
  at jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
  at java.lang.reflect.Method.invoke(Method.java:580)
  at com.carrotsearch.randomizedtesting.RandomizedRunner.invoke(RandomizedRunner.java:1758)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$8.evaluate(RandomizedRunner.java:946)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$9.evaluate(RandomizedRunner.java:982)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$10.evaluate(RandomizedRunner.java:996)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleSetupTeardownChained$1.evaluate(TestRuleSetupTeardownChained.java:48)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at org.apache.lucene.tests.util.TestRuleThreadAndTestName$1.evaluate(TestRuleThreadAndTestName.java:45)
  at org.apache.lucene.tests.util.TestRuleIgnoreAfterMaxFailures$1.evaluate(TestRuleIgnoreAfterMaxFailures.java:60)
  at org.apache.lucene.tests.util.TestRuleMarkFailure$1.evaluate(TestRuleMarkFailure.java:44)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$StatementRunner.run(ThreadLeakControl.java:390)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl.forkTimeoutingTask(ThreadLeakControl.java:843)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$3.evaluate(ThreadLeakControl.java:490)
  at com.carrotsearch.randomizedtesting.RandomizedRunner.runSingleTest(RandomizedRunner.java:955)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$5.evaluate(RandomizedRunner.java:840)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$6.evaluate(RandomizedRunner.java:891)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$7.evaluate(RandomizedRunner.java:902)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleStoreClassName$1.evaluate(TestRuleStoreClassName.java:38)
  at com.carrotsearch.randomizedtesting.rules.NoShadowingOrOverridesOnMethodsRule$1.evaluate(NoShadowingOrOverridesOnMethodsRule.java:40)
  at com.carrotsearch.randomizedtesting.rules.NoShadowingOrOverridesOnMethodsRule$1.evaluate(NoShadowingOrOverridesOnMethodsRule.java:40)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleAssertionsRequired$1.evaluate(TestRuleAssertionsRequired.java:53)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at org.apache.lucene.tests.util.TestRuleMarkFailure$1.evaluate(TestRuleMarkFailure.java:44)
  at org.apache.lucene.tests.util.TestRuleIgnoreAfterMaxFailures$1.evaluate(TestRuleIgnoreAfterMaxFailures.java:60)
  at org.apache.lucene.tests.util.TestRuleIgnoreTestSuites$1.evaluate(TestRuleIgnoreTestSuites.java:47)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$StatementRunner.run(ThreadLeakControl.java:390)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl.lambda$forkTimeoutingTask$0(ThreadLeakControl.java:850)
  at java.lang.Thread.run(Thread.java:1583)

```
test/framework/src/main/java/org/elasticsearch/test/rest/ESRestTestCase.java
Set<String> requiredSameVersionClusterWarnings = new HashSet<>();
        Set<String> allowedWarnings = new HashSet<>();
        private final Set<String> testNodeVersions;
        VersionSensitiveWarningsHandler(Set<String> nodeVersions) {