Inconsistent state reporting (rsyslog-forwarder-ha)?

I hope I can gain some enlightenment here. Why do most of my rsyslog-forwarder-ha units show unknown status, while a couple report active?

  mysql-syslog/0                    unknown   idle              192.168.200.236
  mysql-syslog/1*                   unknown   idle              192.168.200.229
  neutron-api-syslog/1              active    idle              192.168.200.209                     Unit is ready
  neutron-api-syslog/0*             unknown   idle              192.168.200.228
  neutron-gateway-syslog/1*         unknown   idle              192.168.200.180
  neutron-gateway-syslog/0          unknown   idle              192.168.200.191
  nova-cc-syslog/5                  unknown   idle              192.168.200.176
  nova-cc-syslog/4*                 unknown   idle              192.168.200.185
  nova-compute-syslog/3             unknown   idle              192.168.200.37
  nova-compute-syslog/1             unknown   idle              192.168.200.162
  nova-compute-syslog/0             unknown   idle              192.168.200.178
  nova-compute-syslog/2             unknown   idle              192.168.200.188
  nova-compute-syslog/4*            unknown   idle              192.168.200.182
  openstack-dashboard-syslog/1      active    idle              192.168.200.241                     Unit is ready
  openstack-dashboard-syslog/0*     unknown   idle              192.168.200.183
  placement-syslog/4*               unknown   idle              192.168.200.36
  placement-syslog/5                unknown   idle              192.168.200.186

Many thanks in advance!