Managing HP Serviceguard for Linux, Tenth Edition, September 2012

• cmwbemd—WBEM daemon
• cmproxyd—proxy daemon
Each of these daemons logs to the Linux system logging files. The quorum server daemon
logs to the user specified log file, such as, /usr/local/qs/log/qs.log file on Red
Hat or /var/log/qs/sq.log on SUSE and cmomd logs to /usr/local/cmom/log/
cmomd.log on Red Hat or /var/log/cmom/log/cmomd.log on SUSE.
NOTE: The file cmcluster.conf contains the mappings that resolve symbolic
references to $SGCONF, $SGROOT, $SGLBIN, etc, used in the pathnames in the
subsections that follow. See “Understanding the Location of Serviceguard Files” (page 156)
for details.
Configuration Daemon: cmclconfd
This daemon is used by the Serviceguard commands to gather information from all the
nodes within the cluster. It gathers configuration information such as information on
networks and volume groups. It also distributes the cluster binary configuration file to all
nodes in the cluster. This daemon is started by the internet daemon, xinetd(1M).
Parameters are in the /etc/xinetd.d/hacl-cfg and /etc/xinetd.d/
hacl-cfgudp files. The path for this daemon is $SGLBIN/cmclconfd.
Cluster Daemon: cmcld
This daemon determines cluster membership by sending heartbeat messages to cmcld
daemons on other nodes in the Serviceguard cluster. It runs at a real time priority and
is locked in memory. The cmcld daemon sets a safety timer in the kernel which is used
to detect kernel hangs. If this timer is not reset periodically by cmcld, the kernel will
cause a system reboot This could occur because cmcld could not communicate with
the majority of the cluster’s members, or because cmcld exited unexpectedly, aborted,
or was unable to run for a significant amount of time and was unable to update the
kernel timer, indicating a kernel hang. Before a system reset resulting from the expiration
of the safety timer, messages will be written to syslog, and the kernel’s message buffer,
if possible, and a system dump is performed.
The duration of the safety timer depends on the cluster configuration parameter
MEMBER_TIMEOUT, and also on the characteristics of the cluster configuration, such as
whether it uses a quorum server or a cluster lock (and what type of lock) and whether
or not standby LANs are configured.
For further discussion, see “What Happens when a Node Times Out” (page 87). For
advice on setting MEMBER_TIMEOUT, see Cluster Configuration Parameters (page 103).
For troubleshooting, see “Cluster Re-formations Caused by MEMBER_TIMEOUT Being
Set too Low” (page 300).
cmcld also manages Serviceguard packages, determining where to run them and when
to start them. The path for this daemon is: $SGLBIN/cmcld.
34 Understanding Serviceguard Software Components