KAFKA-17146 Include note to remove migration znode #620
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| of the brokers can become the new old-style controller. Additionally, run | ||
| <code>get /migration</code> followed by <code>rmr /migration</code> to clear the | ||
| migration state from ZooKeeper. This will allow you to re-attempt the migration | ||
| in the future. The data read from "/migration" can be useful for debugging. |
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We also need to update it in L4147 (Migrating brokers to KRaft row)
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oh, I don't notice this comment. apache/kafka#16770 is merged. I will sync the changes back to kafka repo if it needs
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I have commented the corresponding JIRA to understand in which state the user rollbacks the cluster to restart the migration because I tried this scenario more times without deleting the /migration znode and it worked fine.
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Thanks @showuon, added the second mention. I wonder why we have this duplication? 🤔
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I wonder why we have this duplication?
it seems we list all directions for reverting for each migration phase. That is a bit verbose, but they are useful. However, it is weird to use "table format" to display so much texts. Maybe we should to a bit refactor for it. Also, the same direction can have its hyperlink to be shared in different migration phase.
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I file jira for it (https://issues.apache.org/jira/browse/KAFKA-17271)
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@mumrah -- can this PR be merged? |
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It's still not clear to me why this removal is needed. I ran migration then rollback then migration and so on several times without the need for deleting such znode. |
When reverting the ZK migration, we must also remove the
/migrationZNode in order to allow the migration to be re-attempted in the future.