libvirt users - Mar 2017 - Re: libvirt-guests and time sync on autostart vms

I have a host running a few guests all configured to autostart.
I'm also using libvirt-guests to suspend the guests when the host
restarts or shuts down
When the host comes back up I see a bunch of log messages  -
Resuming guest vm01 already active
Resuming guest vm02 already active

I guess this is because libvirt autostarts the guests when it starts
and before libvirt-guests has a chance
to start them.
I didn't think this is an issue until I noticed the time on the guests
is totally out of sync.
SYNC_TIME=1 is enabled in the conf file but this doesn't seem to work
I can see from the code at libvirt-guests.sh that the time sync
function will only run if the guest is started by libvirt-guests ans
will be skipped for guests that are already running

So I'm not sure if this is a bug in libvirt-guests.sh or if I'm doing
something wrong by using both libvirt-guests and autostart.
I assume libvirt-guests will always resume guests on proper reboot but
I'm think if there is any unexpected failure where guests weren't
properly suspended before boot I still want them to come backup when
the server boots

Regards,
Yoni

ıuoʎ <yonjah@gmail.com> writes:
> I have a host running a few guests all configured to autostart.
> I'm also using libvirt-guests to suspend the guests when the host
> restarts or shuts down
I have a similar setup. I solved it by writing a small daemon that syncs
system time from RTC time if the error is larger than 10 seconds. This
guarantees that my VM time will be in sync with the host very fast. If
I'd run ntpd it would take minutes for the resumed VM to notice that
something happened.

On Mon, Mar 20, 2017 at 9:58 PM, Timo Juhani Lindfors
<timo.lindfors@iki.fi> wrote:
> ıuoʎ <yonjah@gmail.com> writes:
>> I have a host running a few guests all configured to autostart.
>> I'm also using libvirt-guests to suspend the guests when the host
>> restarts or shuts down
>
> I have a similar setup. I solved it by writing a small daemon that syncs
> system time from RTC time if the error is larger than 10 seconds. This
> guarantees that my VM time will be in sync with the host very fast. If
> I'd run ntpd it would take minutes for the resumed VM to notice that
> something happened.
Yea I created another systemd service that will sync the time of all
running machines on host boot.
I was just wondering if I was missing something with libvirt-guests
and autostart.
I haven't noticed any issues with the time discrepancies on running
guests so I hope this will be enough.