Understanding Rolling Upgrades
- Last Updated: April 15, 2026
- 1 minute read
- MarkLogic Server
- Version 11.0
- Documentation
A rolling upgrade incrementally installs a later version of MarkLogic Server host by host. There is no need to take down the whole cluster to install the later version on each host.
During a rolling upgrade, when the cluster has more than one version of MarkLogic Server running, it is called a mixed-version cluster. On a mixed-version cluster, the features in the newer version of MarkLogic Server are not available. So, you may have to change some of your application code to work in both versions before starting the rolling upgrade. For example, JavaScript code may need modification (because of the new version of V8 for server-side JavaScript) before you commit the upgrade. Once the whole cluster has been committed to the new version, the cluster is no longer in mixed-version state, and the new features are available.
The primary Security, Schema, and auxiliary forests must be on the same host, and that host must be the first host that you upgrade when upgrading a cluster.
Note:
In a mixed-version cluster, before the upgrade has been committed, the node that has been upgraded will be read-only. This status applies only to server configuration and not to content databases. This status prevents any configuration changes from the node. Do not make any configuration changes until you have finished upgrading the entire cluster.