i had a quick look into the source code. The following line in DistUpgrade/DistUpgradeConfigParser.py: print c.getListFromFile("Sources","ValidMirrors")
suggests that my initial guess was right. (I have not verified the following carefully - it is just an assumption, but a very likely one) The update-manager searches in sources.list for a known mirror and then does not find one because my mirror is not listed in DistUpgrade/mirrors.cfg. Then it uses a default value (archive.ubuntu.com main). As it is a very common situation to have a local linux / ubuntu mirror at a university to limit the incoming traffic, this should probably be improved. -- restricted component lost from sources.list during upgrade https://launchpad.net/bugs/68467 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs