Best Path to Migrate from RHEL 7 Front-End to RHEL 9 Front-End

Background/Layout of Systems:

RHEL 7 Cluster
standalone front-end - openneb01
storage back-end - GlusterFS mounted via NFS to the datastores

RHEL 9 Cluster
standalone front-end - openneb02
storage back-end - Ceph mounted via NFS to the datastores

I’ve looked through a lot of documentation and I’m not sure what the best plan of action is. I want all of the configurations (Network, users, ACLs, etc.), the images, templates, etc. as well as the VMs to be transferred to the new cluster.

I’m sure the configs will be easy to transfer as they all should just be files but I’m not sure where they live on the server itself (i.e., if I can just scp from openneb01 to openneb02 and restart opennebula for the config will take).

I’m not sure if the VM transfer is even possible. I’m guessing I can copy the datastore data from Gluster to Ceph with rsync, but I’m not sure if OpenNebula will even pick that up and be able to see/read the VMs.

Any insight is appreciated!

Can’t you upgrade your rhel7 frontend to rhel9 while upgrading the OpenNebula packages as well ? The configurations you can manage with onecfg and the database with onedb for backup and restore purposes.

If you’d like to transfer the frontend01 to frontend02 you could hack these things along with the opennebula install, by restoring the database and the config, and also ensuring that the storage is perceived as the database expects it.