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10.4.2. Capturing the Core When the Daemon Crashes

By default, the /etc/init.d/functions script blocks core files from daemons called by /etc/init.d/rgmanager. For the daemon to create application cores, you must enable that option. This procedure must be done on all cluster nodes that need an application core caught.
For creating a core file when the rgmanager daemon crashes, edit the /etc/sysconfig/cluster file. The DAEMONCOREFILELIMIT parameter allows the daemon to create core files if the process crashes. There is a -w option that prevents the watchdog process from running. The watchdog daemon is responsible for rebooting the cluster node if rgmanager crashes and, in some cases, if the watchdog daemon is running then the core file will not be generated, so it must be disabled to capture core files.
Restart rgmanager to activate the new configuration options:
service rgmanager restart


If cluster services are running on this cluster node, then it could leave the running services in a bad state.
The core file will be written when it is generated from a crash of the rgmanager process.
ls /core*
The output should appear similar to the following:
Move or delete any old cores files under the / directory before restarting rgmanager to capture the application core. The cluster node that experienced the rgmanager crash should be rebooted or fenced after the core is captured to ensure that the watchdog process was not running.