I was able to reproduce this issue. The problem occurs when safe-rm is
installed.
How to reproduce using lxc:
lxc launch images:ubuntu/18.04 bughunt
lxc exec bughunt bash
once you're inside the container run:
apt install ubuntu-release-upgrader-core safe-rm
do-release-upgrade
answer yes so
This issue occured again today when upgrading another server from 18.04
to 20.04
here is a snippet and i'll try to guess what may be happening
==
Stopping some services possibly affected by the upgrade (will be restarted
later):
cron: stopping...done.
Unpacking libc6:amd64
Public bug reported:
do-release-upgrade from bionic to focal has broken for me on at least 9 servers
during release upgrade. perl tries to load /lib/x86_64-linux-gnu/libcrypt.so.1
,which is deleted at this point,
and the upgrade fails.
I always manage to complete the upgrade by copying
