Upgrade to Squeeze
1) Since Wheezy (7.0) will uninstall Postgres 8.3 you need to upgrade the database first, see DB upgrade.
2) Make sure your existing CanIt installation is up-to-date:
3) Now upgrade the OS to Wheezy:
Then you'll see messages scroll by, as the machine downloads, unpacks, and re-starts assorted services. (This all only delays mail during the re-start phase).
3) Since Debian has changed the way it distributes firmware, you may need additional packages. Even if you don't need them, installing them won't hurt so we recommend running:
apt-get install firmware-linux-free firmware-linux-nonfree firmware-bnx2 firmware-bnx2x
(That's all one long line in case it got line-wrapped by a mail reader.)
If, after running this command, you still receive warnings about "Possible missing firmware", please reply with the exact error message. You can check for unusual modules by perusing the output of lsmod.
4) Reboot the machine. To check if mail is flowing use the following:
(tail -f /var/log/mail.log or wherever they are to see if working)
NOTE: The above commands are for a single machine. If you are upgrading a cluster, then you should modify the steps as follows, starting with the DataBase machine:
a) Before every command above, run:
b) After the command in step (4), run:
c) Also, all commands should be run in parallel. That is, run (a) and then (1) on all machines, then (a) and (2) on all machines, and so on.