Monitoring hosts behind a load balancer

On Tue, Jun 15, 2010 at 1:03 PM, Ryan Novosielski <user-ae4522577e16@xymon.invalid>wrote:

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Steve Holmes wrote:

On Tue, Jun 15, 2010 at 12:42 PM, Ralph Mitchell
<user-00a5e44c48c0@xymon.invalid <mailto:user-00a5e44c48c0@xymon.invalid>> wrote:

    I used to have some scripts that would make SOAP requests to an F5
    to get the pools and pool member status.  I no longer have access to
    that system, but I may have a backup at home.

    I based my scripts on a bunch of example programs in the F5 SDK.
     IIRC, I altered a couple of the perl scripts to output lines like:

         pool1 server1 OK
         pool1 server2 DOWN
         etc...

    Then you just run around a loop reading the lines and sending BB
    status messages.

    As long as your F5 is checking the servers occasionally, this
    approach works OK.

    Ralph Mitchell


    On Tue, Jun 15, 2010 at 12:07 PM, Steve Holmes <user-ec1bf77b1b44@xymon.invalid
    <mailto:user-ec1bf77b1b44@xymon.invalid>> wrote:

        Greetings, I'm monitoring several Solaris 10 servers which are
        behind an F5 load balancer. One of the features of the F5 is
        that it answers pings for all of the hosts behind it, even if
        they are all down. Has anyone devised a method of testing the
        servers for being alive in this context? There are no other
        network based tests being done. Yes, all of the other tests
        eventually go purple in Xymon, but we'd like to know that the
        hosts are down when that happens.

        Thanks,
        Steve Holmes
        ITaP/Purdue University


Thanks! I'll check with the F5 admin to see if this might be doable.
Steve

It would not surprise me though if this is exactly what the F5 devmon
template gives you via SNMP. Might be worth a check. If you just
download the tar and look at the templates directory under F5, you'll
the OID's file should tell you what's monitored. Hate to see duplication
of effort. :)

You may well be right.  I couldn't tell, back then, because my ex-employer
had a habit of blocking SNMP traffic.  That might have changed now that
they're under new ownership...  :)

Ralph Mitchell