[Pkg-libvirt-maintainers] Bug#598149: Bug#598149: libvirt-bin: autostart fails on reboot

[Jean-Louis Dupond]

On Mon, 27 Sep 2010 15:07:02 +0200, Guido Günther <agx at sigxcpu.org> wrote:
> tag 598149 +unreproducible
> thanks
> 
> 
> So your vm autostarts either when
> 
> - fixing the /dev/net/tun permissions to 0666 - everything fine here - I
>   understand that.
>
If I chmod /dev/net/tun to 0666 before libvirt starts, it works.
> or
> 
> - when restarting libvirtd after the boot - I don't understand that one.
So when the node is booted, I restart libvirt-bin.
(cloud:~# /etc/init.d/libvirt-bin restart
 Restarting libvirt management daemon: /usr/sbin/libvirtd.)

Then the guests are started without any issue. Still I didn't change
anything in the config/permissions between the boot & the restart of
libvirt.

> 
> * Are you using cgroups (though this shouldn't change anything about the
>   device permissions)?
I'm using no cgroups.
> * Any chance there's another self compiled libvirtd around that could
get
>   picked up?
Did never compile it myself. So there is no manual libvirt installation.
> 
> When I try to reproduce your problem here it's 100% consistent: the
> device comes up with 0640 and the vm won't start. After restarting
> libvirtd the device is still 0640 and the vm still won't start (as
> expected). When I change the permissions of /dev/net/tun to 0666
> everything works fine and the vm gets autostarted on daemon restart.
Can you create a guest device that uses tap0 for example.
Then create tap0 with the owner of libvirt. And then try to start the
guest.

This is my current setup. /etc/network/interfaces creates the tap devices
with the libvirt owner, so that libvirt shouldn't have access to
/dev/net/tun.
> 
> Could you doublecheck the permissions of /dev/net/tun when the vm runs?
The permissions are always:
crw-rw---- 1 root uml-net 10, 200 Sep 27 13:54 /dev/net/tun

> Cheers,
>  -- Guido