package uvtool-libvirt (not installed) failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

From log:

Setting up uvtool-libvirt (0~bzr99-0ubuntu1) ...
2016/11/14 18:40:59 socat[16105] E connect(5, AF=1 "/var/run/libvirt/libvirt-sock", 31): No such file or directory
libvirtd does not appear to be listening on "/var/run/libvirt/libvirt-sock".
On Ubuntu, libvirtd is managed with the "libvirt-bin" upstart job.
Repair libvirtd, then reconfigure uvtool-libvirt with:
    sudo apt-get -f install
dpkg: error processing package uvtool-libvirt (--configure):
 subprocess installed post-installation script returned error exit status 1

Thank you for taking the time to report this bug and helping to make Ubuntu better.

It looks like libvirtd was not running at the time of an upgrade, and this caused uvtool-libvirt's postinst to fail. So this is a libvirt bug, not a uvtool bug. Reassigning.

We've seen a few cases of libvirtd failing to start. I wonder if this is related?

Quoting Robie Basak (<email address hidden>):
> Thank you for taking the time to report this bug and helping to make
> Ubuntu better.
>
> It looks like libvirtd was not running at the time of an upgrade, and
> this caused uvtool-libvirt's postinst to fail. So this is a libvirt bug,
> not a uvtool bug. Reassigning.

Wait, what? Perhaps he purposely had disabled it on purpose?

> We've seen a few cases of libvirtd failing to start. I wonder if this is
> related?

There could well be a libvirt bug as well, but if postinst fails ungracefully
if libvirt is stopped isn't that a packaging bug in uvtool-libvirt?

On 2016-11-15 06:52 AM, Serge Hallyn wrote:
> Wait, what? Perhaps he purposely had disabled it on purpose?

I may have done just that, but I can't remember. I was eager to switch
to LXD in Ubuntu 16.04 instead of using LXC and uvtool in Ubuntu 14.04.

I was surprised that it made the upgrade fail, though, and also
surprised it prompted me to file a bug report. I thought it was just
going to send an automated crash report.

I just rebooted, removed all of the orphaned packages, and cleaned up
after the upgrade myself, and everything seems fine now.

Maybe it's related to this problem:

KVM + Xenial Server. libvirt-bin won't configure
http://askubuntu.com/questions/762924/kvm-xenial-server-libvirt-bin-wont-configure#763935

I had to do something similar to get libvirt-bin started again:

$ sudo systemctl stop apparmor.service
$ sudo apt-get install --reinstall qemu-kvm libvirt-bin
$ sudo systemctl start apparmor.service
$ sudo systemctl restart libvirt-bin

and then:

$ sudo apt-get install --reinstall uvtool uvtool-libvirt

Now it all seems to be working again.

Serge said:

> There could well be a libvirt bug as well, but if postinst fails ungracefully
if libvirt is stopped isn't that a packaging bug in uvtool-libvirt?

I disagree. uvtool-libvirt requires libvirtd to be running, and libvirt-bin is expected to ship it running. If a user intervenes by stopping libvirtd or otherwise disabling it, I think the user gets to keep the pieces. Otherwise, what should uvtool-libvirt do gracefully that isn't surprising to the user? The point of a postinst failure is to point out to the user that the package won't work.

John, I think we may have some issue with libvirtd not running as a bug in libvirt packaging. I've seen more than one occurrence of this, but unfortunately we don't have a reliable reproducer.