Managing Serviceguard A.11.20, March 2013

Generic Resource Assistant Daemon: cmresourced
This daemon is responsible to set and get the status/value of generic resources configured as part
of the package and influence the availability of the package based on the availability of the
resource.
Generic resources allows custom defined monitors to be integrated. It provides better control,
options, and flexibility in terms of getting and setting the status of a resource.
This daemon is used by the Serviceguard commands cmgetresource(1m) and
cmsetresource(1m) to get or set the status/value of a simple/extended generic resource
configured in a package and is local to a node. This daemon runs on every node on which cmcld
is running.
Service Assistant Daemon: cmserviced
This daemon forks and execs any scripts or processes required by the cluster daemon, cmcld.
There are two type of forks that this daemon carries out:
• Executing package run and halt scripts
• Launching services
For services, cmcld monitors the service process and, depending on the number of service retries,
cmcld either restarts the service through cmserviced or it causes the package to halt and moves
the package to an available alternate node.
Quorum Server Daemon: qs
Using a Quorum Server is one way to break a tie and establish a quorum when the cluster is
re-forming; the other way is to use a cluster lock. See “Cluster Quorum to Prevent Split-Brain
Syndrome” and “Cluster Lock ” (page 47).
The Quorum Server, if used, runs on a system external to the cluster and is started by the system
administrator, not by Serviceguard. It is normally started from /etc/inittab with the respawn
option, which means that it automatically restarts if it fails or is killed. All members of the cluster
initiate and maintain a connection to the Quorum Server; if it dies, the Serviceguard nodes will
detect this and then periodically try to reconnect to it. If there is a cluster re-formation while the
Quorum Server is down and tie-breaking is needed, the re-formation will fail and all the nodes will
halt (system reset). For this reason it is important to bring the Quorum Server back up as soon as
possible.
For more information about the Quorum Server software and how it works, see the latest version
of the HP Serviceguard Quorum Server release notes at http://www.hp.com/go/
hpux-serviceguard-docs under HP Serviceguard Quorum Server Software
Network Manager Daemon: cmnetd
This daemon monitors the health of cluster networks, and performs local LAN failover. It also
handles the addition and deletion of relocatable package IP addresses for both IPv4 and IPv6.
Lock LUN Daemon: cmdisklockd
If a lock LUN is being used, cmdisklockd runs on each node in the cluster and is started by
cmcld when the node joins the cluster.
Utility Daemon: cmlockd
Runs on every node on which cmcld is running (though currently not actually used by Serviceguard
on HP-UX systems).
Serviceguard Architecture 43