Tuning the Sun Cluster HA for Sybase ASE Fault Monitor

The Sun Cluster HA for Sybase ASE fault monitor queries the Sybase ASE server to determine server health.

The Sun Cluster HA for Sybase ASE fault monitor monitors only the Adaptive server. The fault monitor does not monitor auxiliary servers.

The Sun Cluster HA for Sybase ASE fault monitor is contained in the resource that represents Sybase ASE. You create this resource when you register and configure Sun Cluster HA for Sybase ASE. For more information, see Registering and Configuring Sun Cluster HA for Sybase ASE.

System properties and extension properties of this resource control the behavior of the fault monitor. The default values of these properties determine the preset behavior of the fault monitor. The preset behavior should be suitable for most Sun Cluster installations. Therefore, you should tune the Sun Cluster HA for Sybase ASE fault monitor only if you need to modify this preset behavior.

Tuning the Sun Cluster HA for Sybase ASE fault monitor involves the following tasks:

• Setting the interval between fault monitor probes

• Setting the timeout for fault monitor probes

• Defining the criteria for persistent faults

• Specifying the failover behavior of a resource

Perform these tasks when you register and configure Sun Cluster HA for Sybase ASE. For more information, see the following sections:

• Registering and Configuring Sun Cluster HA for Sybase ASE

• Tuning Fault Monitors for Sun Cluster Data Services in Sun Cluster Data Services Planning and Administration Guide for Solaris OS

The Sun Cluster HA for Sybase ASE fault monitor consists of the following processes.

• Main fault-monitor process

• Database-client fault probe

Main Fault-Monitor Process

The fault monitor process diagnoses errors and checks statistics. The monitor labels an operation successful if the following conditions occur.

• The database is online.

• The activity check returns no errors.

• The test transaction returns no errors.

If an operation fails, the main process checks the action table for an action to perform and then performs the predetermined action. If an operation fails, the main process can perform the following actions.

1. Restarting the resource on the current node

2. Restarting the resource group on the current node

3. Failing over the resource group to the next node on the resource group's node list

These actions execute external programs as separate processes in the background.

The server fault monitor also scans the Adaptive_Server_Log file and corrects any errors that the scan identifies.

Database-Client Fault Probe

The database-client fault probe performs activity checks and test transactions. The extension property Connect_string specifies an account that performs all of the database operations. The extension property Probe_timeout sets the time-out value that the probe uses to determine the time that has elapsed in a successful database probe.

Obtaining Core Files for Troubleshooting

To facilitate troubleshooting of unexplained DBMS timeouts, you can enable the fault monitor to create a core file when a probe timeout occurs. The contents of the core file relate to the fault monitor process. The fault monitor creates the core file in the / directory. To enable the fault monitor to create a core file, use the coreadm command to enable set-id core dumps. For more information, see the coreadm(1M) man page.