My Proxmox server has all VMs / CTs stored on an NFS share.
What is the best way to back up all VM config, reinstall Proxmox, and then restore the VM configs (all while leaving the disk images on the same NFS server).
why do you want to do this, instead of in-place upgrading[0]?
anyway, if you really wanna do it;
1. take backup of /etc/pve
2. reinstall proxmox
3. copy over vm, ct, storage and other needed configs (change the name/ip address accordingly if it's a different one)