To upgrade a single Couchbase Server node, first back it up and then install the software.

Steps for upgrading a Couchbase Server node explained in this section are identical for an online upgrade (for a node that has been removed from the cluster) or an offline upgrade (for a node that has not yet been added to the cluster).

1. Download Couchbase Server software.
2. Back up data for that server. To back up an existing Couchbase Server installation, use cbbackup.
3. Back up the server-specific configuration files. While the upgrade scripts perform a backup of the configuration and data files, make your own backup of these files as the best practices rule.
4. Stop Couchbase Server instance.
5. Check your host name configuration. If you have deployed Couchbase Server in a cloud service, or if you are using hostnames rather than IP addresses, you must verify that the hostname has been configured correctly before performing the upgrade.
6. Check for required components and, if needed, install them. This ensures that Couchbase Server can be upgraded and migrates the existing data files.
7. Perform the installation upgrade for your platform.