Faults that each Sun Cluster HA for SAP DB fault monitor detects are described in the subsections that follow.
The SAP DB fault monitor detects the following faults in SAP DB:
A status of the SAP DB database instance that is not ONLINE, for example, OFFLINE or ADMIN
Unexpected termination of the parent kernel process of the SAP DB database instance
The SAP DB fault monitor also detects the unavailability of SAP xserver. This fault monitoring supplements the fault monitoring that the SAP xserver fault monitor provides.
If the SAP DB fault monitor detects that SAP xserver is unavailable twice within the retry interval, the SAP DB fault monitor restarts SAP DB. By restarting SAP DB, the fault monitor ensures that the SAP DB database fails over to another node when SAP xserver is persistently unavailable.
The SAP xserver fault monitor detects following faults:
Unavailability of SAP xserver. Unavailability of SAP xserver is also detected by the SAP DB fault monitor.
Persistent system errors. A persistent system error is a system error that occurs four times within the retry interval. If a persistent system error occurs, the fault monitor restarts SAP xserver.
To minimize the disruption that transient faults in a resource cause, a fault monitor restarts the resource in response to such faults. For persistent faults, more disruptive action than restarting the resource is required:
For the SAP DB resource, the fault monitor fails over the resource to another node. The SAP DB resource is a failover resource.
For the SAP xserver resource, the fault monitor takes the resource offline. The SAP xserver is a scalable resource.