Health Check

Assuming this is a HTTP monitor you can always use telnet from the F5 to the server on the relevant port. Additionally, the [tmsh] run util test-monitor ‘name’ command will give you more detailed feedback on what is causing the failure (compared to the GUI).

 

 

Can you post the Pool and Monitor configuration (suitably 'anonymised')?

Hi Steve.

 

 

Here is config

 

 

 

pool mysite1 {

 

monitor all health1

 

members {

 

x.x.x.x:http {}

 

y.y.y.y:http {}

 

}

 

}

 

 

 

 

monitor health1 {

 

defaults from tcp

 

recv "STATUS=Ok"

 

send "GET /check.aspx\r\n"

 

}

 

 

 

 

 

 

when browse individual server like http://x.x.x.x/check.aspx and http://y.y.y.y/check.aspx . i get response "STATUS=OK" . but map this pool . y.y.y.y is seems to down.

 

 

 

Telnet only show.port is open or not. How this type of health check from F5 ?.

 

I would suggest you change the monitor 'defaults from' to http. If that doesn't help;

 

 

1) Depending on your version \r\n may or not be required. What version are you running?

 

2) Telnet to y.y.y.y and then enter this;

 

-telnet y.y.y.y 80 [ENTER]

 

-GET /check.aspx HTTP/1.1[ENTER]

 

Do this on x.x.x.x too and see what the difference is, if any

 

3) Execute [tmsh] run util test-monitor ‘name’ against each server and again compare the differences

 

 

Are these two web servers very difference? Running difference web server software or versions?

just in case if you have not yet seen these articles.

 

 

sol3224:HTTP health checks may fail even though the node is responding correctly

 

http://support.f5.com/kb/en-us/solutions/public/3000/200/sol3224.html

 

 

Troubleshooting Ltm Monitors by Aaron

 

https://devcentral.f5.com/wiki/advdesignconfig.troubleshootingltmmonitors.ashx

 

 

hope this helps.