[libvirt-users] Libvirt newer than 2.1.0 doesnt start up

[Laine Stump]

On 10/17/2016 10:32 AM, Rene Pasing wrote:
> Hi all,
>
> I have some problems with libvirt >2.1.0 (so 2.2.0 and 2.3.0): I have a
> working environment using libvirt 2.1.0 with 1 domain (called "mail")
> and one network (called "default6"), both are autostarted. I have no
> problems with this environment using libvirt 2.1.0, everything works great.
>
> But after (testwise) updating to libvirt 2.2.0 or 2.3.0, libvirt doesn't
> start up anymore.
>
> Some investigations showed that apparently my "default6" network is the
> problem. Libvirt is starting correctly after disabling all autostarts.
> When I then virsh' into the system daemon and type "net-start default6",
> then nothing happens and that command just hangs infinitely.
>
> Further information, relevant log entries and e.g. the used default6.xml
> configuration file can be found here, as I first thought it would be a
> configuration error from my side:
> https://bbs.archlinux.org/viewtopic.php?pid=1653221
>
> Do you maybe have an idea what could be going on? Or do you maybe need
> more information, and if yes, which exactly?

Nothing seems unusual about your config, and your troubleshooting so far 
eliminates some common problems. I've just tried starting an IPv6 
network with a libvirtd built from the latest sources (but on Fedora 24) 
and don't experience your problem.

I guess at this point what's most likely to get closer to the root of 
the problem would be to attach gdb to the hung libvirtd process and run 
"thread apply all bt". Presumably one of the threads will be waiting on 
a system call to return and that may give a further clue.