This bug report isn't really useful if you don't say which version of ubuntu-release-upgrader you were using. There were changes made to it recently to display specific error messages depending on which partition is full.
ubuntu-release-upgrader (1:17.10.7) artful; urgency=medium * DistUpgrade/DistUpgradeController.py: Provide better instructions when an upgrade is aborted due to a lack of free space in a partition. (LP: #1721882) ** Changed in: ubuntu-release-upgrader (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1740383 Title: do-release-upgrade doesn't report useful info if a partition is full To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1740383/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs