during shutdown libvirt-guests.sh shouldn't run if libvirtd isn't running

[Doug Smythies]

The libvirtd service being started during boot doesn't mean it is still running during shutdown.
libvirt-guests.sh waits around for 10 seconds trying to communicate with it, re-trying once per second.
The desire is that it either doesn't run at all or it checks if libvirtd is even running before wasting the 10 seconds.

As a use case example:
I often disable extraneous services so as to get my test server to be very "idle", much more idle than a typical user, particularly with a desktop type GUI, can achieve. I can easily re-boot 50 times in a day, and get hit by this 10 seconds every time.

Example:

Dec 01 13:52:13 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 10
Dec 01 13:52:14 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 9
Dec 01 13:52:15 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 8
Dec 01 13:52:16 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 7
Dec 01 13:52:17 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 6
Dec 01 13:52:18 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 5
Dec 01 13:52:19 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 4
Dec 01 13:52:20 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 3
Dec 01 13:52:21 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 2
Dec 01 13:52:22 goom-i5 libvirt-guests.sh[3717]: Unable to connect to libvirt currently. Retrying .. 1Can't connect to default. Skipping.

This occurs on my old 16.04 test server and a newly created 20.04 test server.

[Doug Smythies (dsmythies)]

For example, this seems to work well:

doug@goom-i5:~/config/usr/lib/libvirt$ diff libvirt-guests.sh.original libvirt-guests.sh
114,124c114,126
< i=${CONNECT_RETRIES}
< while [ $i -gt 0 ]; do
< run_virsh "$uri" connect 2>/dev/null
< if [ $? -eq 0 ]; then
< return 0;
< fi
< sleep ${RETRIES_SLEEP}
< eval_gettext "Unable to connect to libvirt currently. Retrying .. \$i"
< i=$(($i-1))
< done
< eval_gettext "Can't connect to \$uri. Skipping."
---
> if `pidof libvirtd 1>/dev/null`; then
> i=${CONNECT_RETRIES}
> while [ $i -gt 0 ]; do
> run_virsh "$uri" connect 2>/dev/null
> if [ $? -eq 0 ]; then
> return 0;
> fi
> sleep ${RETRIES_SLEEP}
> eval_gettext "Unable to connect to libvirt currently. Retrying .. \$i"
> i=$(($i-1))
> done
> eval_gettext "Can't connect to \$uri. Skipping."
> fi

[Christian Ehrhardt  (paelzer)]

Hi Doug,
thanks for the report - and yes I agree it shouldn't waste time on that, but it isn't that easy IMHO.

Users can configure in /etc/default/libvirt-guests for any URI including remote ones.
Therefore there can be no local check to the service that will make a clear decision if we can skip trying to connect.

But I'd expect that 99,9..% of the users have still "defult" in the URI and then we could do the suggested.

I've submitted a patch for this [1], lets see what others think.

[1]: https://www.redhat.com/archives/libvir-list/2019-December/msg00079.html

[Christian Ehrhardt  (paelzer)]

New revision of the fix was accepted upstream.
This will be merged with the libvirt that gets into 20.04

[Launchpad Janitor (janitor)]

This bug was fixed in the package libvirt - 6.0.0-0ubuntu1

---------------
libvirt (6.0.0-0ubuntu1) focal; urgency=medium

  * Merged with Debian 5.6.0-4 from experimental and v6.0.0 from upstream
    Among many other new features and fixes this includes fixes for:
    - LP: #1859253 - rbd driver fails to create a new volume
    - LP: #1858341 - rbd driver does not list all volumes in pool
    - LP: #1845506 - Libvirt snapshot doesn't update apparmor profile
    - LP: #1854653 - slow libvirt-guests.sh during shutdown if service is off
    - LP: #1848229 - enable ppc64el to use ccf-assist feature
    - LP: #1853315 - Enable CPU Model Comparison and Baselining on s390x
    - LP: #1853317 - CCW IPL support to boot from ECKD DASDs
    - LP: #1859506 - security: AppArmor profile fixes for swtpm
    Remaining changes:
    - Disable libssh2 support (universe dependency)
    - Disable firewalld support (universe dependency)
    - Set qemu-group to kvm (for compat with older ubuntu)
    - Additional apport package-hook
    - Autostart default bridged network (As upstream does, but not Debian).
      In addition to just enabling it our solution provides:
      + do not autostart if subnet is already taken (e.g. in guests).
      + iterate some alternative subnets before giving up
    - d/p/ubuntu/Allow-libvirt-group-to-access-the-socket.patch: This is
      the group based access to libvirt functions as it was used in Ubuntu
      for quite long.
      + d/p/ubuntu/daemon-augeas-fix-expected.patch fix some related tests
        due to the group access change.
      + d/libvirt-daemon-system.postinst: add users in sudo to the libvirt
        group.
    - ubuntu/parallel-shutdown.patch: set parallel shutdown by default.
    - Update Vcs-Git and Vcs-Browser fields to point to launchpad
    - Update README.Debian with Ubuntu changes
    - Enable some additional features on ppc64el and s390x (for arch parity)
      + systemtap, zfs, numa and numad on s390x.
      + systemtap on ppc64el.
    - d/p/ubuntu/ubuntu_machine_type.patch: accept ubuntu types as pci440fx
    - Further upstreamed apparmor Delta, especially any new one
      Our former delta is split into logical pieces and is either Ubuntu only
      or is part of a continuous upstreaming effort.
      Listing related remaining changes in debian/patches/ubuntu-aa/:
    - fix autopkgtests
      + d/t/control, d/t/smoke-qemu-session: fixup smoke-qemu-session by making
        vmlinuz available and accessible (Debian bug 848314)
      + d/t/control: fix smoke-qemu-session by ensuring the service will run
        installing libvirt-daemon-system
      + d/t/smoke-lxc: fix smoke-lxc by ignoring potential issues on destroy as
        long as the following undefine succeeds
      + d/t/smoke-lxc: use systemd instead of sysV to restart the service
    - dnsmasq related enhancements
      + run dnsmasq as libvirt-dnsmasq (LP: 1743718)
      + d/libvirt-daemon-system.postinst: add libvirt-dnsmasq user and group
      + d/libvirt-daemon-system.postrm: remove libvirt-dnsmasq user and group
        on purge
      + d/p/ubuntu/dnsmasq-as-priv-user: write dnsmasq config with user
        libvirt-dnsmasq and adapt t...