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neeeewbie's avatar
neeeewbie
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Mar 25, 2021
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http2 monitor using eav

Hi guys

I need your help!

 

we check pool member using http2 monitor using eav but I can't find reverse option on eav

how to enable reverse option on eav ??

 

I referenced https://devcentral.f5.com/s/articles/Using-a-BIG-IP-EAV-external-monitor-to-monitor-HTTP-2-h2c-servers

 

thanks

application delivery
BIG-IP
  • jaikumar_f5's avatar
    jaikumar_f5
    Mar 28, 2021

    Actually in my opinion, EAV (external) monitors never had the reverse option. Because that's totally breaks the logic of std ouput which marks the node up. Reverse option could be found on http / https monitors, i've seen it. But not on the external monitor. The script run, writes to standard output, if thats true, pool member is marked up. There' no reverse option here.

     

    Feel free to correct otherwise.

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  • jaikumar_f5's avatar
    jaikumar_f5
    Icon for MVP rankMVP
    Mar 28, 2021

    Actually in my opinion, EAV (external) monitors never had the reverse option. Because that's totally breaks the logic of std ouput which marks the node up. Reverse option could be found on http / https monitors, i've seen it. But not on the external monitor. The script run, writes to standard output, if thats true, pool member is marked up. There' no reverse option here.

     

    Feel free to correct otherwise.

    • neeeewbie's avatar
      neeeewbie
      Icon for MVP rankMVP
      Mar 29, 2021

      thank you for sharing your knowledge

       

      do you know other way for using reverse option?

  • alven_kim's avatar
    alven_kim
    Icon for Altostratus rankAltostratus
    Sep 13, 2021

    There is a concept of EAV in the link below.

    EAV only determines the status-up/down of stdout.

    If the string is returned to stdout, it will unconditionally state-up.

    If there's no stdout, state-down.

     

    Unfortunately, I also failed to use the receive-enable-string/disable-string function using the monitor of h2c.

     

    <EAV Concept> - https://support.f5.com/csp/article/K1561

    Important: Any node that fails to meet the EAV criteria should not be sent to stdout. If you create an EAV script that displays a node as up for a positive response, but also displays down for a negative response, the bigd process will interpret both responses as up.