divijvaidya commented on code in PR #578: URL: https://github.com/apache/kafka-site/pull/578#discussion_r1496098814
########## 37/upgrade.html: ########## @@ -18,8 +18,85 @@ <script><!--#include virtual="js/templateData.js" --></script> <script id="upgrade-template" type="text/x-handlebars-template"> + <h4><a id="upgrade_3_7_0" href="#upgrade_3_7_0">Upgrading to 3.7.0 from any version 0.8.x through 3.6.x</a></h4> -<h4><a id="upgrade_3_6_0" href="#upgrade_3_6_0">Upgrading to 3.6.0 from any version 0.8.x through 3.5.x</a></h4> + <h5><a id="upgrade_370_zk" href="#upgrade_370_zk">Upgrading ZooKeeper-based clusters</a></h5> + <p><b>If you are upgrading from a version prior to 2.1.x, please see the note in step 5 below about the change to the schema used to store consumer offsets. + Once you have changed the inter.broker.protocol.version to the latest version, it will not be possible to downgrade to a version prior to 2.1.</b></p> + + <p><b>For a rolling upgrade:</b></p> + + <ol> + <li>Update server.properties on all brokers and add the following properties. CURRENT_KAFKA_VERSION refers to the version you + are upgrading from. CURRENT_MESSAGE_FORMAT_VERSION refers to the message format version currently in use. If you have previously + overridden the message format version, you should keep its current value. Alternatively, if you are upgrading from a version prior + to 0.11.0.x, then CURRENT_MESSAGE_FORMAT_VERSION should be set to match CURRENT_KAFKA_VERSION. + <ul> + <li>inter.broker.protocol.version=CURRENT_KAFKA_VERSION (e.g. <code>3.5</code>, <code>3.4</code>, etc.)</li> + <li>log.message.format.version=CURRENT_MESSAGE_FORMAT_VERSION (See <a href="#upgrade_10_performance_impact">potential performance impact + following the upgrade</a> for the details on what this configuration does.)</li> + </ul> + If you are upgrading from version 0.11.0.x or above, and you have not overridden the message format, then you only need to override + the inter-broker protocol version. + <ul> + <li>inter.broker.protocol.version=CURRENT_KAFKA_VERSION (e.g. <code>3.5</code>, <code>3.4</code>, etc.)</li> + </ul> + </li> + <li>Upgrade the brokers one at a time: shut down the broker, update the code, and restart it. Once you have done so, the + brokers will be running the latest version and you can verify that the cluster's behavior and performance meets expectations. + It is still possible to downgrade at this point if there are any problems. + </li> + <li>Once the cluster's behavior and performance has been verified, bump the protocol version by editing + <code>inter.broker.protocol.version</code> and setting it to <code>3.6</code>. + </li> + <li>Restart the brokers one by one for the new protocol version to take effect. Once the brokers begin using the latest + protocol version, it will no longer be possible to downgrade the cluster to an older version. + </li> + <li>If you have overridden the message format version as instructed above, then you need to do one more rolling restart to + upgrade it to its latest version. Once all (or most) consumers have been upgraded to 0.11.0 or later, + change log.message.format.version to 3.6 on each broker and restart them one by one. Note that the older Scala clients, + which are no longer maintained, do not support the message format introduced in 0.11, so to avoid conversion costs + (or to take advantage of <a href="#upgrade_11_exactly_once_semantics">exactly once semantics</a>), + the newer Java clients must be used. + </li> + </ol> + + <h5><a id="upgrade_370_kraft" href="#upgrade_370_kraft">Upgrading KRaft-based clusters</a></h5> + <p><b>If you are upgrading from a version prior to 3.3.0, please see the note in step 3 below. Once you have changed the metadata.version to the latest version, it will not be possible to downgrade to a version prior to 3.3-IV0.</b></p> + + <p><b>For a rolling upgrade:</b></p> + + <ol> + <li>Upgrade the brokers one at a time: shut down the broker, update the code, and restart it. Once you have done so, the + brokers will be running the latest version and you can verify that the cluster's behavior and performance meets expectations. + </li> + <li>Once the cluster's behavior and performance has been verified, bump the metadata.version by running + <code> + ./bin/kafka-features.sh upgrade --metadata 3.7 + </code> + </li> + <li>Note that cluster metadata downgrade is not supported in this version since it has metadata changes. + Every <a href="https://github.com/apache/kafka/blob/trunk/server-common/src/main/java/org/apache/kafka/server/common/MetadataVersion.java">MetadataVersion</a> + after 3.2.x has a boolean parameter that indicates if there are metadata changes (i.e. <code>IBP_3_3_IV3(7, "3.3", "IV3", true)</code> means this version has metadata changes). + Given your current and target versions, a downgrade is only possible if there are no metadata changes in the versions between.</li> + </ol> + + <h5><a id="upgrade_370_notable" href="#upgrade_370_notable">Notable changes in 3.7.0</a></h5> + <ul> + <li>Client APIs released prior to Apache Kafka 2.1 are now marked deprecated in 3.7 and will be removed in Apache Kafka 4.0. See <a href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-896%3A+Remove+old+client+protocol+API+versions+in+Kafka+4.0">KIP-896</a> for details and RPC versions that are now deprecated. + </li> + <li>Java 11 support for the Kafka broker is also marked deprecated in 3.7, and is planned to be removed in Kafka 4.0. See <a href="https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=284789510">KIP-1013</a> for more details. Note that clients can continue to use JDK >= 8 to connect to Kafka brokers. + </li> + <li>Early access of the new simplified Consumer Rebalance Protocol is available, and it is not recommended for use in production environments. + You are encouraged to test it and provide feedback! + For more information about the early access feature, please check <a href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-848%3A+The+Next+Generation+of+the+Consumer+Rebalance+Protocol">KIP-848</a> and the <a href="https://cwiki.apache.org/confluence/display/KAFKA/The+Next+Generation+of+the+Consumer+Rebalance+Protocol+%28KIP-848%29+-+Early+Access+Release+Notes">Early Access Release Notes</a>. + </li> Review Comment: nit "... and provide feedback at https://issues.apache.org/jira/browse/KAFKA-16061" -- 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: dev-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org