I am having exactly same problem while doing network upgrade. Part of the log is: Checking package manager Reading package lists: Donehardy-security/universe Packages: 98 98 Building dependency tree: Done Building dependency tree: Done Building dependency tree: Done
Invalid package information After your package information was updated the essential package 'ubuntu-minimal' cannot be found any more. This indicates a serious error, please report this bug against the 'update-manager' package and include the files in /var/log/dist-upgrade/ in the bugreport. Restoring original system state Aborting Reading package lists: Done Building dependency tree: Done Building dependency tree: Done -- ubuntu-minimal cannot be found - herd 4 upgrade fails https://bugs.launchpad.net/bugs/86133 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs