Check the crash dump directory for a crash dump created after the switchover had occurred. The time the dump was collected can be found by referring to the time stamp using, for example, the "ls(1)" command.
If a crash dump after the switchover is found
Save the crash dump.
If a crash dump after the switchover is not found
If the failed node is restartable, manually collect a crash dump before restarting it.
Information
A crash dump is stored as a file on the node in which the error occurred.
If your guest OS has been forcefully stopped by the shutdown facility or the guest OS has been panicked in the environment where the KVM virtual machine function is used, the crash dump will be stored in the following directory for the host OS.
/var/crash/<shutdown time of the guest OS (YYYYMMDDHHMMSS)>.<Domain name for the guest OS>.core
Example: node1 was forcefully stopped at 12:34:56 on 20th April, 2011
/var/crash/20110420123456.node1.core