Configuring the WSM using Device Manager

Script-based health checking  

Script-based health checks run a sequence of tests to dynamically verify application and content availability. You can configure the WSM to send a series of ASCII health check requests to real servers or real server groups and monitor the responses.

Note: Only TCP services can be health checked using scripts, since UDP protocols are usually not ASCII based. Note: You can enable script-based health checks from JDM, but the actual scripts must be configured from the CLI.

Script-based health checking provides:

• Multiple command format
• Checking for any return string
• Testing for availability of different applications
• Testing for availability of multiple domains or Web sites
• 1024 bytes per script per WSM
• 16 scripts per WSM
• Approximately 10 to 15 health check statements (HTTP Get and Expect strings) per script

The script-based health check is structured to perform the following:

1. Open a connection to a specific TCP port.
2. Send an ASCII request to the server.
3. Expect an ASCII string.

The WSM searches each response packet for this string. If it is not found before the real server health check interval expires, the server does not pass the expect step and fails the health check.

4. Close the connection.

A script can contain any number of these commands, up to the allowable number of characters that a script supports.

See also:

• Configuring script-based health checks
• Direct server return health checking
• ICMP health checking
• ARP health checking
• Link health checking
• TCP health checking
• Modifying the health check interval and retries
• Application health checking
• About health checking