Screen crashed during do-release-upgrade, won't resume

[Mackenzie Morgan]

I was running "do-release-upgrade -d" to get from 10.04 to 12.04. Partway through, screen (running as byobu) disappeared. I can see that the upgrade is still running and trying to ask me questions I can't answer because I can't reconnect to the screen session.

Expected Result: upgrade runs inside screen and completes
Actual Result: screen crashes making the currently-running upgrade inaccessible to user

<snip earlier upgrade log>
Installing new version of config file /etc/byobu/socketdir ...
Setting up fakeroot (1.18.2-1) ...
Setting up dctrl-tools (2.18ubuntu1) ...
Setting up diffstat (1.54-1) ...
Setting up distro-info-data (0.8ubuntu0.1) ...
Setting up distro-info (0.8.2) ...
Setting up python-distro-info (0.8.2) ...
-----------------------------------------------------------------------------
0*&$ shell 1@$ shell 2@$ shell 3-@$ shell 4@$ shell 5@$ shell maco Menu:<F9>
 U 2012-06-01 22:56:17
Error: Cannot find master process to attach to!
maco@lucid:~$
maco@lucid:~$
maco@lucid:~$ screen -r
There is a screen on:
 3498.pts-0.lucid (04/09/2012 09:21:02 AM) (Dead ???)
Remove dead screens with 'screen -wipe'.
There is no screen to be resumed.

maco@lucid:~$ ps -ef | grep upgrade
maco 9969 17012 0 23:35 pts/6 00:00:00 grep --color=auto upgrade
root 26066 1 0 18:50 ? 00:00:00 SCREEN -e \0\0 -L -c screenrc -S ubuntu-release-upgrade-screen-window /tmp/tmphNKbs8/precise --mode=server --frontend=DistUpgradeViewText
root 28183 28167 0 22:56 pts/9 00:00:00 whiptail --backtitle Package configuration --title Configuring postgresql-common --output-fd 11 --nocancel --msgbox Obsolete major version 8.4??The PostgreSQL version 8.4 is obsolete, but the server or client ?packages are still installed. Please install the latest packages ?(postgresql-9.1 and postgresql-client-9.1) and upgrade the existing ?clusters with pg_upgradecluster (see manpage).??Please be aware that the installation of postgresql-9.1 will ?automatically create a default cluster 9.1/main. If you want to ?upgrade the 8.4/main cluster, you need to remove the already existing?9.1 cluster (pg_dropcluster --stop 9.1 main, see manpage for ?details).??The old server and client packages are no longer supported. After the?existing clusters are upgraded, the postgresql-8.4 and ?postgresql-client-8.4 packages should be removed.??Please see /usr/share/doc/postgresql-common/README.Debian.gz for ?details. 25 74

[Axel Beckert (xtaran)]

AFAIK screen -ls considers a screen session dead at least when the server crashed but the socket is still there.

I wonder if the opposite ("SCREEN" server still there as your ps output shows, but the socket is gone) could be a reason, too, i.e. if the move from /var/run to /run could be the cause. (Just an idea which should be checked. Will test that. :-)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.