Managing Serviceguard Seventeenth Edition, First Reprint December 2009

Single-Node Operation
In a multi-node cluster, you could have a situation in which all but one node has failed,
or you have shut down all but one node, leaving your cluster in single-node operation.
This remaining node will probably have applications running on it. As long as the
Serviceguard daemon cmcld is active, other nodes can rejoin the cluster.
If the Serviceguard daemon fails when in single-node operation, it will leave the single
node up and your applications running. (This is different from the loss of the
Serviceguard daemon in a multi-node cluster, which halts the node with a TOC, and
causes packages to be switched to adoptive nodes.) It is not necessary to halt the single
node in this scenario, since the application is still running, and no other node is currently
available for package switching.
You should not try to restart Serviceguard, since data corruption might occur if another
node were to attempt to start up a new instance of the application that is still running
on the single node.
Instead of restarting the cluster, choose an appropriate time to shut down the
applications and reboot the node; this will allow Serviceguard to restart the cluster
after the reboot.
Disabling Serviceguard
If for some reason you want to disable Serviceguard on a system, you can do so by
commenting out the following entries in /etc/inetd.conf:
hacl-cfg dgram udp wait root /usr/lbin/cmclconfd cmclconfd -p
hacl-cfg stream tcp nowait root /usr/lbin/cmclconfd cmclconfd -c
Then force inetd to re-read inetd.conf:
/usr/sbin/inetd -c
You can check that this did in fact disable Serviceguard by trying the following
command:
cmquerycl -n nodename
where nodename is the name of the local system. If the command fails, you have
successfully disabled Serviceguard.
362 Cluster and Package Maintenance