4.1.0 HP PolyServe Matrix Server administration guide (T5392-96073, October 2010)

A SHARED_FILESYSTEM device monitor is associated with a specific PSFS filesystem.
The monitor probes the filesystem at periodic intervals to determine the filesystem
health. The probe attempts to open and read a file located on the filesystem. When
you configure the monitor, you can specify the file to be read, or you can let Matrix
Server create a file for this purpose.
A SHARED_FILESYSTEM device monitor attempts to be active on each server specified
in its configuration. The device monitor probe reports an UP status for the filesystem
only if it is mounted and file content can be read from the filesystem.
When you create a SHARED_FILESYSTEM device monitor, be sure to configure the
following advanced options:
• Virtual hosts. Select any virtual hosts that should fail over if the monitor probe
reports a DOWN status for the filesystem.
• Servers. Select all servers that have mounted the filesystem and are running the
applications associated with the virtual hosts.
You might also want to create Start, Stop, or Recovery scripts to customize the
behavior of the monitor.
Custom device monitor
A CUSTOM device monitor can be used if the built-in device types are not sufficient
for your needs. Custom device monitors can be particularly useful when integrating
Matrix Server with a custom application.
When you create a CUSTOM monitor, you will need to supply the probe script. In
the script, probe commands should determine the health of the device as necessary.
If the device is operating normally, the probe script should exit with exit status zero.
If the device is not operating normally, the probe script should exit with a non-zero
exit status. Matrix Server interprets the non-zero exit status as a failure of the device
and takes the appropriate action.
See Chapter 17 on page 233 for information about developing probe scripts for
custom monitors and integrating monitors with custom applications.
Device monitors and failover
When a device monitor is configured for failover and the probe reports a failure,
Matrix Server attempts to relocate any virtual hosts that depend on the monitored
device to a healthier server:
Configure device monitors220