Comment 38 for bug 1878548

Verified focal-proposed with the following output:

$ apt-cache policy masakari-monitors-common
masakari-monitors-common:
  Installed: 9.0.0-0ubuntu0.20.04.2
  Candidate: 9.0.0-0ubuntu0.20.04.2
  Version table:
 *** 9.0.0-0ubuntu0.20.04.2 500
        500 http://archive.ubuntu.com/ubuntu focal-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     9.0.0-0ubuntu0.20.04.1 500
        500 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
     9.0.0~b3~git2020041013.e225e6d-0ubuntu1 500
        500 http://archive.ubuntu.com/ubuntu focal/main amd64 Packages

Tested fencing communication between a compute host and all masakari/corosync units e.g.

# do this on all masakari units
juju run -a masakari -- sudo iptables -I INPUT -p tcp -s 10.0.0.10 --sport 3121 -j REJECT

# then wait for compute host 10.0.0.10 to get rebooted which it did although the notification was not sent but that feels unrelated to this patch/bug.
$ openstack notification list

# From below we confirm that only compute0 was rebooted
$ juju ssh nova-compute/0 uptime
 12:20:32 up 24 min, 1 user, load average: 0.65, 0.82, 1.00
Connection to 10.0.0.10 closed.
$ juju ssh nova-compute/1 uptime
 12:20:37 up 2:23, 1 user, load average: 0.70, 0.85, 1.02
Connection to 10.0.0.47 closed.
$ juju ssh nova-compute/2 uptime
 12:20:41 up 2:23, 1 user, load average: 0.64, 0.71, 0.89
Connection to 10.0.0.31 closed.