The upgrade from v11 to v12 went fine. No issues and everything worked flawlessly.
The upgrade to v13 however, did not go as well.
I wanted to let Veeam know what went wrong for me. Maybe someone else could use some of the solutions as well.
All issues are mostly resolved one way or another.
I had to remove my Veeam-configuration-backup-to-tape system (repo->file->tape);
Then two (out of four) application-aware VM backups failed;
I've fixed this by manually installing the Guest Agent on those servers.
The Linux Volume level backup failed;
Had to re-implement kb4732(rebuild the veeamsnap module).
All OLVM VMs backup failed;
Temporary fix was to allow all ports, after which it suddenly worked again, although there are no new ports required in v13... (we have an ACL inplace between backup server and targets). I still need to find out which port I need to allow - on my todo list.
I have made Powershell scripts to e-mail me which tapes to take out, these failed as well.
When manually running the script, I get "The Powershell module Veeam.Backup.Powershell won't load. This may be due to corruption or not installed. Quitting." Nice and descriptive, right? I needed Reddit to tell me it was because it required Powershell 7! This fixed it. (run with 'pwsh' instead of 'powershell' in Task Scheduler) It's not mentioned in any (upgrade)documentation as far as I can search.
Besides how well or not I've implemented everything, I would've expected a smoother experience to be honest.
Backup to tape is now also fixed. I had to register the B&R server as a File Server under Inventory -> Unstructured Data.
After that I could browse again to the repository as a file source.
Warning -> opinion incoming!
One thing I forgot to mention. I really dislike the new GUI icons. They are too thin and thus hard too see. I cannot imagine the designer asking someone whose sight is impaired if this is a good design. Because it isn't IMO. The lines are too thin which makes all icons useless for button identification, which I did kinda use them for.
Please take a new look at the design from the perspective of people with sight problems. At least give me an option to revert to the old icons.
The Midnight Green theme does help me personally, so there's that!
We have no clients in our network that we can reach through zero-trust. Besides that, we hold no actual (work-related) data on the devices for security reasons.
So, luckily I guess, I don't have (or better: can't have) that issue.