Nortel Networks WEB OS 212777 - Manual (Page 228)

Web OS 10.0 Application Guide
228 n Chapter 10: Health Checking
212777-A, February 2002
Script Example 2: GSLB URL Health Check
In earlier Web OS releases, each remote Global Server Load Balancing site’s virtual server IP
address was required to be a real server of the local switch. Each switch sends a health check
request to the other switch’s virtual servers that are configured on the local switch. The health
check is successful if there is at least one real server on the remote switch that is up. If all real
servers on the remote switch are down, the remote real server (a virtual server of a remote
switch) will respond with an HTTP Redirect message to the health check.
Using the scriptable health check feature, you can set up health check statements to check all
the substrings involved in all the real servers.
Site 1 with Virtual Server 1 and the following real servers:
n
Real Server 1 and Real Server 2: “images”
n
Real Server 3 and Real Server 4: “html”
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Real Server 5 and Real Server 6: “cgi” and “bin”
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Real Server 7 (which is Virtual Server 2): “any”
Site 2 with Virtual Server 2 and the following real servers:
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Real Server 1 and Real Server 2: “images”
n
Real Server 3 and Real Server 4: “html”
n
Real Server 5 and Real Server 6: “cgi” and “bin”
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Real Server 7 (which is Virtual Server 2): “any”
A sample script is shown below:
/cfg/slb/group x/health script2/content none
/cfg/slb/adv/script2
open 80
send "GET /images/default.asp HTTP/1.1\\r\\nHOST: 192.192.1.2\\r\\n\\r\\n"
expect "HTTP/1.1 200"
close
open 80
send "GET /install/default.html HTTP/1.1\\r\\nHOST: 192.192.1.2\\r\\n\\r\\n"
expect "HTTP/1.1 200"
close
open 80
send "GET /script.cgi HTTP/1.1\\r\\nHOST: www.myurl.com \\r\\n\\r\\n"
expect "HTTP/1.1 200"
close