| SYSTEM INFORMATION | |
|---|---|
| OS type and version | DEBIAN 11 |
| Webmin version | 2.30.3 |
| Virtualmin version | 7.30.8 |
| Webserver version | Apache 2.4.62 |
| Related packages | SUGGESTED |
Has anyone already upgraded their Virtualmin setup from Debian 11 to Debian 12?
Would be great to hear if it’s a smooth ride - or if it’s one of those “better wait and see” situations. Always good to know before diving in.
I know there were some ‘bumps’ with new installs when 12 came out. Some of the changes have made me leery of trying an in place upgrade. If possible migrate to a new install and see how it works. Then migrate back.
We use Virtualmin with Debian 12, however this was NOT by means of an upgrade from Debian 11.
Generally speaking, you should take a backup of your system before attempting a major release upgrade.
From what I’ve read, upgrading between major releases (11 to 12 for instance) has become a bit more stable over the past few release for Debian. However, depending on how many third party packages you rely on, and how much customizations you’ve made to the system after installing Debian 11 will often determine how well the upgrade will occur.
Typically, when an upgrade is performed third party repos are disabled, and any package that was installed in Debian 11 that is not supported in Debian 12 will be removed from the system during the upgrade or simply ignored (but may not work after the upgrade).
Personally, because aside from potential hiccups with upgrades based on the above mentioned, and the fact that upgrades often leave behind artifacts from the previous install, I prefer to launch a new system, do a “clean” install of both the new distro release, and Virtualmin, then conduct a restore from a previous install.
Whether you use the Virtualmin Backup/Restore features for the recovery of your Virtual Servers or use a more crude method of manually restoring Virtual Servers on the new system is your choice, and both methods have their pros/cons depending on what you’re attempting to accomplish.
Bottom line, create a backup before attempting any major distro release upgrade, this way you have a means of restoring your system if things don’t go well, which then offers you a means of doing the upgrade via another method such as the one mentioned above.
*** you can hire me, or another contractor in the community to assist you with a professional upgrade/migration if you don’t feel up to the challenge yourself. ***
I upgraded 15-20 servers within the first week that 12 come out.
As mentioned from others, you should always have a proper working backup in place, or even better, snapshots of your VM so you can easily rollback in case things go wrong.
Debian has always had solid upgrade routines.
Last time there was an issue because of Debians own design choice was when going from 5 → 6 (or was it 6 → 7?) but since then it’s been smooth.
From 7 → 8 was problematic on mailservers running Dovecot because of a major version upgrade in which Dovecot broke their own configs by changing the entire config file, making it non-compatible with the old ones.
These things are all mentioned in the Debian handbook, so if you have large (and old) installs read through those before to be prepared for any major changes.
Fun fact, I still have one server running that was installed on Debian 3.1 and upgraded untill now. It’s been migrated from physical to virtual, moved hardware and so on since of course, but it’s a slim install and still running smoothly 
PS: BACKUP BACKUP BACKUP!