My server had been on 10.04 for a long time. With the upcoming 11.10 that means it would be 3 major releases behind. So I decided it was time to upgrade.
I ssh'ed to the server then upgraded via command line. First I made sure that all packages were up to date
> sudo apt-get update
> sudo apt-get upgrade
> sudo apt-get dist-upgrade
Now the release upgrade
> sudo do-release-upgrade
It returned with no new release. The Ubuntu Community website provided help. By default, update-manager only looks for LTS releases. Since my server version (10.04) was already LTS, there was no further LTS release to upgrade. I needed to change the setting.
> sudo vi /etc/update-manager/release-upgrades
to change to Prompt=normal
> sudo do-release-upgrade
Now it could find a release to upgrade. However, it gave a warning since I used SSH to connect to the server. Basically, the upgrade process may affect sshd, thus ssh-client. To prevent connectivity issues half-way through the upgrade, another sshd on port 1022 will be started as a backup.
I acknowledged the warning and proceeded. Fortunately there was no issue at all. My ssh session wasn't killed half-way through. Now my server is running 10.10. My next step is to upgrade to 11.04.
