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Forum Discussion

Michaelyang's avatar
Michaelyang
Icon for Cirrostratus rankCirrostratus
Nov 10, 2022

pool monitor issue

Hello, I encountered a problem here... I set up the oracle external monitor will suddenly fail, manually build a similar test but normal again. Here is monitor setting Today, I changed back...
application delivery
CA_Valli's avatar
CA_Valli
Icon for MVP rankMVP
Nov 10, 2022

Your external monitor will check for output being returned to stdout in order to mark a pool member available.
If no data was returned, it will mark pool member down. 

To manually run external monitor and check for output, you can move to  /config/filestore/files_d/Common_d/external_monitor_d/ where all of your external monitor scripts are stored, check for script name (I noticed BIG-IP appends some sort of versioning to the files) and then run it as as script, passing it the required parameters (I  believe defaults are server ip, L4 port and timeout)  

 

[root@f5:Active:Standalone] common # cd /config/filestore/files_d/Common_d/external_monitor_d/
[root@f5:Active:Standalone] external_monitor_d # ./\:Common\:myexternalmonitor_320535_2 <server ip ex 10.10.10.10> <server port ex. 1813> <timeout ex. 16>

 

 

This will immediately let you know if output is seen or not, or if there are other errors -- for example I noteiced PERL interpreter changing directory when moving to BIG-IPv15 

  • Michaelyang's avatar
    Michaelyang
    Icon for Cirrostratus rankCirrostratus
    Nov 11, 2022

    Hi CA_Valli,

    Thanks for your aply.

    But I find it odd that a node with the original state of down actually UP after switching to another monitor with the same settings...

    And it also happened three times...

     

     

    • CA_Valli's avatar
      CA_Valli
      Icon for MVP rankMVP
      Nov 11, 2022

      As long as your script retrieves anything an answer (so that there is some data in stdout output), external monitor will mark node up... let's say it returns a "KO" message or "connession issue" messege -- those are both non-null strings so monitor will be green.