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Forum Discussion

astokes_6920's avatar
astokes_6920
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Nov 10, 2009

HTTP monitor with HEAD, not GET

While using the following monitor, I'm finding that the web servers are keeping TCP sessions in the TIME_WAIT state, rather than closing them outright.     GET /serverin.html HTTP/1.1\r\nCo...
management
monitoring
L4L7_53191's avatar
L4L7_53191
Icon for Nimbostratus rankNimbostratus
Jun 24, 2012
Yes, although I'm not certain which side of the connection flow you're referring to. I'll assume you're talking about the server side.

 

 

In that case, you'll want to keep both time_wait recycle and re_use enabled, as it'll leave those sockets open as candidates for new connections if the stack deems it necessary. TIME_WAIT is something that the stack really should do, although the duration of that interval (by default 2*MSL) is somewhat a matter of debate, especially behind an LTM with a super smart TCP stack...

 

 

By the way, not all OS's (linux, for one) allow you to tickle the TIME_WAIT interval - you'll see some bad information out there on the web, so tread lightly (e.g. setting the FIN_WAIT2 timer). So it's best to leave recycle/reuse enabled and let the stack sort it out as it needs to.

 

 

HTH,

 

--Matt Cauthorn