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Forum Discussion

SP_266134's avatar
SP_266134
Icon for Nimbostratus rankNimbostratus
Aug 03, 2018

http monitor

Hello guys, I ma trying to set up a monitor http for every 5 min interval. get some file with response code. GET /check HTTP/1.0\r\n\r\n interval 299 sec timeout 301 sec. return string : live Can...
application delivery
BIG-IP
LTM
Chris_Grant's avatar
Chris_Grant
Icon for Employee rankEmployee
Aug 03, 2018

We recommend that you use a 3+1 interval timeout. Keep in mind, we keep sending monitors even when the system is down. A five minute interval is extremely long, but might make sense in your situation. Our default is a five second interval with a sixteen second timeout. In that situation (taking a simple SYN monitor), we would work as follows:

0  sec - SYN
5  sec - SYN
10 sec - SYN
15 sec - SYN
16 sec - we would mark the pool member down here
20 sec - SYN
25 sec - SYN
30 sec - SYN
         SYN/ACK
         ACK - we would mark the pool member up here, unless told otherwise by the config.

If you had an HTTP monitor, there would just be more traffic, and with a 5 minute interval and sixteen minute timeout, we would send a monitor every five minutes and mark the pool member down after sixteen minutes of no response. You would still have only four monitor outstanding, however.