Elasticsearch clusters can usually be upgraded one node at a time so upgrading does not interrupt service. For upgrade instructions, refer to Upgrading to Elastic 8.11.3. Upgrade from 7.x To upgrade to 8.11.3 from 7.16 or an earlier version, you must first upgrade to 7.17, even if you opt to do a full-cluster restart instead of a rolling upgrade. This enables you to use the Upgrade Assistant to id