This document describes how to live-upgrade a Vespa instance. Use this procedure to upgrade without disruption to read or write traffic.

• If upgrading to a new major version, first upgrade to the latest version on the current major, then make sure there are no deprecation warnings when building and deploying the application
• Also make sure to detach nodes as part of the procedure
• Redundancy: for data availability, there must be capacity to take one node per cluster out of service at the time. This procedure relies on that. If the clusters have redundancy=1, or searchable-copies=1, some data is not available (reduced coverage) during the upgrade
\$ vespa-deploy prepare <app> && vespa-deploy activate