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Darren_M_19965's avatar
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Jun 11, 2012

Need some direction Monitor vs iRule to determine to fail over

So, as the title and summary state, I'm looking for some direction here.


I need to know how to accomplish the following.


One can assume the following simple configuration:


OS/Hardware: 2 Windows 2003r2 servers behind an F5.


We'll call them Svr1 and Svr2. They are effectively identical.




The servers are transactional and receive a plain text IP request string on port 1200. Process the request and respond on the same port to the client.


Simplified Sample Request:









Normally, the F5 is weighted so that Svr1 gets all the messages. However, if Svr1, the service, or the port is down I want to fail over to Svr2. Also, if for any reason I get an error code NOT equal to ERRCODE|00000000 I want to fail over as well. And, when the fail over DOES occur, I want to send an email from the F5 notifying of the fault.


So, my question is, which tool set should I use to accomplish this?


Thanks in advance,


Darren M


2 Replies

  • You don't necessarily need a pool monitor (a common monitor for all members). You can have one or more specific monitor(s) per member.


    In your case, define a TCP-type customised monitor for Svr1 with "recv" set to "ERRCODE|00000000" and Scr2 a genetic TCP-type monitor. Set Svr1's "priority" to 1 and Scr2's "priority" to 0 and pool's "min active members" to 1. This will give you the active(Svr1)-standby(Svr2).



    Regarding emails, I don't have experience with that, but I'd say you'd need an iRule to generate a log message that'd be translated into a customised trap. See:


    SOL3727: Configuring custom SNMP traps -


    SOL3667: Configuring alerts to send email notifications -


    SOL11127: Testing SNMP traps on BIG-IP (9.4.x - 11.x) -




    SOL6414: Determining which alerts are pre-configured to trigger an SNMP trap -
  • @epaalx Thank you for your response! Looks like I have a lot of reading to do. I really do appreciate the direction and will look further into the email notification.


    Best regards,


    Darren M