Now that the shiny new Ubuntu 9.04 is available, the servers with packages for 7.10 are closed down. Ok, how to upgrade a server, if you can’t even install the update-manager-core package - because of the missing repositories?
(Backup and) edit your
/etc/apt/sources.list file, comment out any third-party software sources. Replace every occurence of the old distribution name (
gutsy in question) with the new name (
hardy for the latest Long-Time-Support release, or a newer release). Then start a screen, in case your network connection breaks during the upgrade.
(make sure that you don’t see any 404 errors here)
(that’s the old name, the new one is
Reboot your box and voila you should have an upgraded system.