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Forum Discussion

Ken_04_163875's avatar
Ken_04_163875
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Dec 10, 2018

Receive String Not Reconized By Custom HTTP Health Check Monitor

Hi, We're using a custom HTTP monitor for our application that hits a specific URL and checks the response to make sure that it is correct. The F5 is not recognizing the Receive string and thus is m...
application delivery
application health monitoring
LTM
gscholz_370150's avatar
gscholz_370150
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Dec 11, 2018

Have you tried running a tcpdump on port 80 to see exactly how the curl request is formed to get the intended result? Then you could edit the send string accordingly.

 

Ken_04_163875's avatar
Ken_04_163875
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Dec 13, 2018

I have run a tcpdump on this request, and it returns the expected string (picture of Ken pulling out his hair).

 

What I don't understand is a telnet to this URL, with either a 1.0 or 1.1 HTTP request, fails, but a curl, using a 1.0 or 1.1 HTTP request, returns the correct string. Since the URL for the monitor check is hitting a separate war file, that then hits the application to determine it's availability, is it possible that this is considered a redirect (301) and thus telnet and the health monitor fails? There is no evidence of a redirect, either in telnet, curl, the monitor logs, or in a browser hitting the same URL...