@rustylh We really need more information to even begin. What version of XCP-ng are you using? What hardware are you using to run XCP-ng? What is the underlying storage where the VM resides on? What OS is the VM running? How are you taking snapshots, XO? How old was the snapshot? Were the guest utilities installed into the VM? You do know snapshots are not backups, right?

Sorry, I'm asking if I should be good deleting the snapshots

AlmaLinux 8.10

@olivierlambert Dang ok. I waited a few minute then clicked the Connect in XOA for that host and it connected. Not sure what to do really.

So you have to dig in the SMlog to check what's going on

About the xsconsole: sometimes it's not refreshing. You can try to get access to the console, then type "xsconsole" it will start it and you should see it works You must have the master up to date if you want your slave to connect again. I never tried to elect a new master in the middle of the upgrade, I would discourage it. Better shutdown some VMs on the master, upgrade it and you are automatically back on track.

Then try to find anything happening around that time on other hosts, equipment, storage and so on.