Forum Discussion

adharkrader's avatar
adharkrader
Icon for Nimbostratus rankNimbostratus
Aug 31, 2009

Missed monitor counter or log?

Many of our apps get "sick" before they die: they'll miss 1-2 keepalives over a period of hours or days before they miss enough to be marked down. We'd like to know when they're in that condition so we can address the problem before they croak.

 

 

Is there a way to see when things are "dying" but not yet dead? Either a counter on failed monitor checks or an info log message or something... I don't see anything like that in the LOCAL-MIB.

 

 

Any suggestions?

 

 

Thanks - Al
management
monitoring
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Aug 31, 2009
    Hi Al,

     

     

    You could configure a script to run if a pool member is marked down and an alert is logged to /var/log/ltm. See this post for some additional info:

     

     

    Generic command in user_alert.conf

     

    http://devcentral.f5.com/Default.aspx?tabid=53&forumid=32&tpage=1&view=topic&postid=55956

     

     

    And SOL9569:

     

     

    SOL9469: A disabled interface is enabled after a reboot or an mcpd process restart

     

    https://support.f5.com/kb/en-us/solutions/public/9000/400/sol9469.html

     

     

    Aaron
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Aug 31, 2009
    Sorry... I just realised nothing is logged when a single monitor attempt fails--only when a monitor marks a pool member down. So the above suggestions won't help much. You could add a second external monitor to the pool which runs a curl command and logs a message to /var/log/ltm on a single failure. You'd want to set the pool to mark the member up if at least one monitor succeeds so this second monitor won't actually take the pool member out of the rotation. You could then trigger an SNMP trap, email or syslog message to a remote host for single failures. I'd be surprised though if you didn't get a lot of false positives from temporarily busy pool members.

     

     

    Aaron