Why does my health monitor fail?

Thank you very much for your insight. It is still failing though. Forgive my ignorance but what is the best way to test the strings from the F5? ltm monitor http enterprise_heartbeat_mon { defaults-from http destination *:* interval 5 ip-dscp 0 recv 200 send "GET /Enterprise/login.cmdx\r\nHost: nextrelease.sample.com\r\n\r\n" time-until-up 0 timeout 16 }

tcpdump and curl are the best ways to test

Thank you for your assistance. The other issue was the receive string. I was advised I could use header information, thus the "200" recv string. That is incorrect. You have to use something (text, not pictured words) that is actually displayed on page. Once I did that, it worked.

You can use the status line, the response headers, and the HTTP payload to match against.