I want to upgrade to Debian Squeeze and there are quite a few guides out there, but I want to be safe and make sure I don't break my system. Is there a way to check if my current install packages are going to work on Squeeze? If so, how? How can I backup my system to ensure it's okay to upgrade?
migrated from serverfault.com Feb 26 '12 at 16:12
The release notes for squeeze go into detail about the proper proceedures and things to check before the upgrade. You can find the section here: http://www.debian.org/releases/stable/i386/release-notes/ch-upgrading.en.html
I have upgraded a lot of servers from sarge to etch, etch to lenny and lenny to squeeze.
Upgrading to squeeze is a bit of an odd ball in that certain essential things have changed, the way disks are named (using UUIDs instead of device names) and udev as well as an upgrade to grub2.
The procedure always came down to (I prefer to use apt in a shell):
I choose to NOT chainload grub2 using grub but use grub2 right away. This can be a tricky part but just be careful. Ideally grub2 should have been configured and set up correctly but I noticed that's not always the case. To make sure, you can run (you can run it as often as you want):
Then choose your boot disk, say you boot from /dev/sda then you choose /dev/sda to save the boot record. Normally you don't need to choose partitions such as /dev/sda1 unless that's how you booted before.
Reboot again to see if it works ok. If so that's it.
This was just a quick overview and you should definitely read the guides. But after many upgrades to squeeze I found it almost always boiled down to the above.