Having trouble with GNS

I’m trying to use the Global Name Server in a primary and backup server
configuration. In some situations, the two servers do not sync.

Primary is run as server, ‘gns -s’ on node1.

Backup is run as ‘gns -s node1’ on node2.

All the remaining computers are run as clients with ‘gns -c node1 node2’.

When one or the other server is powered down, neither is sync’d on power up