Upgrading RHEL From 8 to 9

To attempt an in-place OS upgrade from RHEL 8 to RHEL 9, follow these steps:

1. Create a full backup of all databases.

2. Stop MarkLogic Server for the entire cluster.

3. Upgrade the OS from RHEL 8 to 9. Follow the standard upgrade procedure for MarkLogic Server along with the RHEL upgrade procedure, Upgrading From RHEL 8 to RHEL 9. According to the RHEL documentation, these are the supported in-place upgrade paths for the OS:

   Source OS	Target OS
   RHEL 8.8	RHEL 9.2
   RHEL 8.10	RHEL 9.4

4. Upgrade MarkLogic Server to version 11.3.1 or higher using the RHEL9 installer in the upgraded machine as described in Upgrading From Previous Releases. In some cases, an in-place upgrade of RHEL will not retain all the applications in the previous systems. See Appendix: Linux Packages regarding dependencies and required libraries before upgrading MarkLogic Server.