I've just upgraded a test Groupwise 2012 system that has been upgraded over time from when it ran on Novell OS. It was until tonight running Groupwise 2012 on OES11.
The primary domain upgraded without a hitch. The secondary was another story. I found the following issues.
I was unable to obtain the ca from the primary domain service. This turned out to be modproxy wasn't enabled on the apache server. It was installed, but just not enabled. I believe I read that if it wasn't installed it would be as part of the install. Maybe there was some special changes to the apache conf file that stopped this process.
The second problem was that the secondary domain had in the Groupwise Object an NSS path /LINUX/usr/novell/sys/Groupwise/Domain. Where as the UNC path was changed to /usr/novell/sys/Groupwise/Domain (Thanks to the TID 7014850) this didn't change the Groupwise object itself. I could find no way of changing this, so I simply created a linux path using a soft link so that /LINUX/usr/novell/sys/Groupwise/Domain pointed to /usr/novell/sys/Groupwise/Domain. I set the UNC path to /LINUX/usr/novell/sys/Groupwise/Domain, rebuilt the database and synced the database using Console One and then tried the upgrade again. Worked like a charm.
Now you think I'd be able to change the domain path in the new Groupwise admin tool for the domain back to just /usr/novell/sys/Groupwise/Domain. But no, it crashes gwadminservice. I'll follow that one up later.
For anyone wondering why /LINUX/usr/novell/sys/Groupwise/Domain, it s a hand over from migration from Novell. I'd normally create a NSS share for the root of the server so I had full access to the server from Windows via NSS.
I hope this helps someone else in their upgrades