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Forum Discussion

JamesR's avatar
JamesR
Icon for Nimbostratus rankNimbostratus
May 06, 2020

HTTP monitor which ignores timeouts

Hi all,   Might be approaching this in the wrong way but I want a way for the application owners to trigger a pool failure by placing a text file on a web server. This is so they are in control w...
application delivery
BIG-IP
LTM
Samir's avatar
Samir
Icon for MVP rankMVP
May 06, 2020

Custom Health monitor is always best option to check send/receive string. Ask application team to create one webpage and monitor that page via F5 HTTP health monitor. Its call ECV (Extended Content Verification) - some info is sent to the server and some info is expected to receive.

 

https://support.f5.com/csp/article/K2167

 

Below Screen will help you to understand the setting.

 

  • JamesR's avatar
    JamesR
    Icon for Nimbostratus rankNimbostratus
    May 06, 2020

    Hi  , thanks for the reply.

    I was hoping to have this centralised that we have a single monitor that is used for holding the service down rather than doing it node-by-node. In the solution we have an 'admin' server that I was hoping to use for this but I'd only want the monitor to be marked as down if the HTTP request returned a 200 and not if it timed out or other things occurred.

    I was working on something like this;

    ltm monitor http /Common/ServiceMonitor {
    defaults-from /Common/http
    description ServiceMonitor
    destination admin.node.ip:80
    send "GET /srvdown.txt HTTP/1.1\r\nHost: bigip.health.check\r\nConnection: Close\r\n\r\n"
    recv "HTTP/1.1 200"
    interval 30
    timeout 60
    reverse enabled
}

    Doesn't look like this is possible though - is that your understanding too?

    Cheers

    • Samir's avatar
      Samir
      Icon for MVP rankMVP
      May 06, 2020

      I believe it should work. Did you try?​

    • JamesR's avatar
      JamesR
      Icon for Nimbostratus rankNimbostratus
      May 06, 2020

      It works unless admin.node.ip is down or timing out then the monitor reports DOWN rather than UP.

    • Samir's avatar
      Samir
      Icon for MVP rankMVP
      May 06, 2020

      No seen these use case so far. Need to do research on these options (transparent and Reverse)​. Thanks