[Pkg-xen-devel] Bug#879751: xen-utils-common: /etc/init.d/xen restart kills running domU qemu processes

[Kojedzinszky Richárd]

Dear Hans,

Thanks for your reply. Actually, the problem is that the script kills ALL 
qemu processes, not only those attached to xen domU domains. I think that 
is a problem.

Would that be nice that a bash upgrade would kill all running bash 
processes? And also, in earlier debian releases, this was not the case, I 
could upgrade the xen-common package without any issues. Of course, a 
whole xen (hypervisor) upgrade might need a reboot, but just a xen-common 
upgrade might not. Right now it seems to me it breaks thing more than it 
helps.

Regards,
Kojedzinszky Richárd
Euronet Magyarorszag Informatika Zrt.

On Sun, 17 Dec 2017, Hans van Kranenburg wrote:

> Date: Sun, 17 Dec 2017 20:08:37 +0100
> From: Hans van Kranenburg <hans at knorrie.org>
> To: 879751 at bugs.debian.org,
>     Richard Kojedzinszky <kojedzinszky.richard at euronetrt.hu>
> Subject: Re: xen-utils-common: /etc/init.d/xen restart kills running domU qemu
>      processes
> 
> Hi Richard,
>
> it's recommended to only actually upgrade xen packages just before you
> want to reboot the system, and when you already stopped all domUs.
>
> This is e.g. a similar situation to upgrading the openvswitch package,
> which will also restart processes and mess up all network interfaces of
> running domUs.
>
> For unattended-updates, you can just stuff "xen" inside your
> Unattended-Upgrade::Package-Blacklist, or if you're not using that you
> can put all xen related packages on hold manually and only forcibly
> include them to be upgraded just before the reboot.
>
> Upgrading the xen packages while domUs are running can result in a wide
> range of scenarios which will cause problems. Solving all of those would
> require more work and adding far more complexity to the packages than
> there's programmers and testers (and hardware to test all scenarios etc)
> available in the Debian project to make that happen currently.
>
> Hans
>