Hi. I wanted to start a thread with all real-life Inplace Upgrade Issues long with their (if known) possible solutions. Also, I want to generally discuss the upgrade process, and if there isn't a lot of potential for improvement, cause in my mind, there are dozens unnecessary and dangerous steps the Upgrade process does for no reason.
So let's start:
1. Check /etc/sysconfig/novell/edir_oes2018_sp3, if it contains 'SERVICE_CONFIGURED="yes"'. If it says "no", the upgrade to oes2018sp3 hasn't finished properly. Most likely, the "yast channel-upgrade-oes" didn't happen or ran into an error that wasn't fixed, and now haunts you. Your server most likely is working fine anyways, but your ugrade will fail miserably. (*)
Solution: Edit the file to read 'SERVICE_CONFIGURED="yes"' *before* attemting the upgrade. If you don't do this, the upgrade process will attempt to add your server to the eDir Tree instead of upgrading it.
(IMNSHO this is a massive bug. Relying on some freely editable, notoriously unreliable config file that has no meaning whatsoever to the operation of the server, to determine if a server is active part of an eDir tree or no is insane. Why not just ask eDir instead?)
Also, when this happens, verify the other OES2018SP3 files in /etc/sysconfig/novell, as most likely some others are wrong.
2. The Upgrade *will* activate the Firewall in all cases, which will block most non-standard traffic. Solution: Obviously to disable the firewall after the upgrade again, or configure it for your needs. I personally consider Server Side Firewalls a completely broken idea.
3. The upgrade will alter your Timesync config massively. If you have multiple time servers configured now, it will only take over the first one, plus, it will add a public SUSE NTP pool to your setup without asking. On top (and this is nasty), it will stop your server from answering to NTP traffic, as the /etc/chrony.conf it creates does not contain an "allow=" line. Many installs do rely on OES Servers as their Time Sources, and they will no longer work after the upgrade.
Solution: Edit /etc/chrony.conf (or use yast) and add back all your servers. Also, remove /etc/chrony.d/pool.conf (that is the public suse server pool you may not want).
4. Less important, but may hit you anyways, especially when you run Groupwise: The Upgrade will reenable postfix when it was disabled before. Solution: Disable postfix again, if e.g your GWIA will no longer listen on port 25, and you need it to listen on more than one IP.
More to come. Feel free to add to the discussion what you have found.