[libvirt] [PATCH] rpm: explicitly enable & start virlockd/virtlogd sockets on install

[Michal Privoznik]

On 07.12.2015 13:58, Daniel P. Berrange wrote:
> On Mon, Dec 07, 2015 at 01:57:20PM +0100, Michal Privoznik wrote:
>> On 07.12.2015 13:55, Daniel P. Berrange wrote:
>>> When installing the libvirt-daemon RPM, we have a %post rule to
>>> enable the libvirtd.service, virtlockd.socket and virtlogd.socket
>>> files. This is only done, however, when the RPM is first installed,
>>> not when upgrading RPMs.
>>>
>>> This adds a separate rule to explicitly enable the virtlockd.socket
>>> and virtlogd.socket units upon RPM upgrade, if libvirtd.service
>>> is marked as enabled.  It also adds a rule to start the socket
>>> units if libvirtd.service is running.
>>>
>>> The downside with taking this approach is that it is impossible
>>> for a user to have libvirtd.service enabled and disable socket
>>> activation, because we'll re-enable it on every upgrade. Similarly
>>> we'll be starting the socket listeners on every upgrade if libvirtd
>>> is running. This is a pretty nasty thing to have to keep in libvirt
>>> for the long term, given this upgrade problem is a one-time only
>>> pain point.
>>>
>>> For this reason I am recommending *NOT* applying this patch to GIT.
>>>
>>> Instead, I think we just have to release note the fact that after
>>> upgrading you should enable the virtlockd.socket unit.
>>>
>>> ---
>>>  libvirt.spec.in | 12 ++++++++++++
>>>  1 file changed, 12 insertions(+)
>>>
>>> diff --git a/libvirt.spec.in b/libvirt.spec.in
>>> index 1f76f24..48e5632 100644
>>> --- a/libvirt.spec.in
>>> +++ b/libvirt.spec.in
>>> @@ -1703,6 +1703,18 @@ if [ $1 -eq 1 ] ; then
>>>          libvirtd.service >/dev/null 2>&1 || :
>>>  fi
>>>          %endif
>>> +
>>> +# In upgrade scenario we must explicitly enable virtlockd/virtlogd
>>> +# sockets, if libvirtd is already enabled and start them if
>>> +# libvirtd is running, otherwise you'll get failures to start
>>> +# guests
>>> +if [ $1 -ge 1 ] ; then
>>> +    /bin/systemctl is-enabled libvirtd.service 1>/dev/null 2>&1 &&
>>> +        /bin/systemctl enable virtlockd.socket virtlogd.socket
>>> +    /bin/systemctl is-active libvirtd.service 1>/dev/null 2>&1  &&
>>> +        /bin/systemctl start virtlockd.socket virtlogd.socket
>>> +fi
>>> +
>>>      %else
>>>          %if %{with_cgconfig}
>>>  # Starting with Fedora 16/RHEL-7, systemd automounts all cgroups,
>>>
>>
>> ACK
> 
> Presumably you didn't read my commit message, or are you ACK'ing my
> suggestion that we *NOT* merge this ?

Well, I think that socket activation is nice feature. But as even DV
pointed out (and I've experienced that too on my non-systemd system)
that it's impossible to start domains without virtlogd enabled. I find
it much worse than depending on a 'nice systemd feature'. Therefore I
think we should merge it.

Michal