This upgrade from lenny to squeeze is not more complexer then the update from etch to lenny.
If you read everything carefully your server will run after upgrade too:)
Before you go on please read the official Debian release notes:
Recording your session:
script -t 2>~/upgrade-squeezestep.time -a ~/upgrade-squeezestep.script
First you should update your running system:
aptitude update && aptitude dist-upgrade
Check the package state:
It will show any packages which have a status of Half-Installed or Failed-Config, and those with any error status.
If you had a kernel upgrade please reboot. After successfully updates replace the sources from lenny to squeeze:
sed -i "s,lenny,squeeze,g" /etc/apt/sources.list
With the -d flag you can only start a download of all necessary packages.
aptitude update && aptitude -d dist-upgrade
If you are on a mailserver you should enable the queue mode and remove greylisting
Accept all these packages:
aptitude update && aptitude install keyring apt aptitude dpkg
Now you can run the full upgrade:
Migrate to dependency based boot sequencing:
Example for a firewall init script:
1 2 3 4 5 6 7 8
### BEGIN INIT INFO # Provides: arno-iptables-firewall # Required-Start: $local_fs $remote_fs $network # Required-Stop: $local_fs $remote_fs $network # Default-Start: S # Default-Stop: 0 6 # Short-Description: Setup iptables firewall configuration ### END INIT INFO
Enable greylisting again:
greylistd-setup-exim4 add && greylistd-setup-exim4 test && /etc/init.d/exim4 restart