cmccabe commented on code in PR #15193: URL: https://github.com/apache/kafka/pull/15193#discussion_r1459486416
########## docs/ops.html: ########## @@ -3992,6 +3979,75 @@ <h3>Finalizing the migration</h3> # Other configs ...</pre> + <h3>Reverting to ZooKeeper mode During the Migration</h3> + <p> + While the cluster is still in migration mode, it is possible to revert to ZK mode. The process + to follow depends on how far the migration has progressed. In order to find out how to revert, + select the <b>final</b> migration step that you have <b>completed</b> in this table. + </p> + <p> + Note that the directions given here assume that each step was fully completed, and they were + done in order. So, for example, we assume that if "Enabling the migration on the brokers" was completed, + "Provisioning the KRaft controller quorum" was also fully completed previously. + </p> + <p> + If you did not fully complete any step, back out whatever you have done and then follow revert + directions for the last fully completed step. + </p> + + <table class="data-table"> + <tbody> + <tr> + <th>Final Migration Section Completed</th> + <th>Directions for Reverting</th> + <th>Notes</th> + </tr> + <tr> + <td>Preparing for migration</td> + <td>The prepartion section does not involve leaving ZK mode. So there is nothing to do in + the case of a revert.</td> + <td></td> + </tr> + <tr> + <td>Provisioning the KRaft controller quorum</td> + <td>Deprovision the KRaft controller quorum, and then you are done.</td> + <td></td> + </tr> + <tr> + <td>Enabling zookeeper.metadata.migration.enable on the brokers</td> + <td>Roll the broker cluster with zookeeper.metadata.migration.enable=false. Then, + deprovision the KRaft controller quorum. Then you are done.</td> + <td></td> + </tr> + <tr> + <td>Migrating brokers to KRaft</td> + <td><p> + Roll the broker cluster with the process.roles configuration omitted, node.id + replaced with broker.id, and the zookeeper.connect configuration set to a valid + value. + </p> + <p> + After this roll is fully complete, perform a second roll where you set + zookeeper.metadata.migration.enable=false. Then, + deprovision the KRaft controller quorum. Then you are done. + </p> + </td> + <td> + Make sure that on the first roll, zookeeper.metadata.migration.enable remains set to + true. <b>Do not set it to false until the second roll.</b> Review Comment: Well, the notes are intended to be read before you perform the revert :) Take a look at the latest version and see what you think. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org