HP StorageWorks Clustered File System 3.6.0 Windows Storage Server Edition Administration Guide (403103-005, January 2008)

Chapter 16: Configure Service Monitors 195
TCP Service Monitor
The generic TCP service monitor defaults to TCP port 0. You should set
the port to the listening port of your server software. The default
frequency of the probe is every 30 seconds. The default time that the
service monitor waits for a probe to complete is five seconds. Because the
service monitor cannot know what to expect from the TCP port
connection, it simply attempts to connect to the specified port. If the
attempt is successful, the service status remains Up.
NOTE: Service monitors using TCP port numbers must be assigned
distinct port numbers. For example, the built-in FTP service
monitor and a generic TCP monitor cannot both attempt to use
TCP port 21. You do not need to specify an IP address because a
service monitor is associated with a virtual host. HP Clustered File
System uses that virtual host IP address in combination with the
TCP port number to create network TCP connections for service
monitors.
Custom Service Monitor
HP Clustered File System provides a
CUSTOM service monitor type that
can be used when the built-in monitor types are not sufficient. Custom
monitors can be particularly useful when integrating HP Clustered File
System with a custom application.
HP Clustered File System treats custom monitors just as it does the built-
in monitors, except that you must supply the probe script. In the script,
probe commands should determine the health of the service as necessary.
If the service is operating normally, the probe script should exit with exit
status zero. If the service is not operating normally, the probe script
should exit with a non-zero exit status. HP Clustered File System will
interpret the non-zero exit status as a failure of the service and then take
the appropriate action. See “Advanced Monitor Topics” on page 226 for
information about developing probe scripts for custom monitors and
integrating monitors with custom applications.