How are your LVM2 volumes configured? Based on that segfault, I would guess that it has something to do with that (and would not necessarily be reproducible if the volume configuration is not similar).
I would have a hard time believing that it has anything to do with our custom Debian packages. However, it might be worth the trouble to try and configure a fresh 16.04 system and upgrading it, then do it again and try upgrading after adding our packages. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1789977 Title: Upgrade from 16.04 to 18.04 crashed, required dpkg --configure -a to recover (multiple machines) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1789977/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
