Forum Discussion

az1441_7592's avatar
Icon for Nimbostratus rankNimbostratus
May 18, 2011

Service Unavailable Notification???

Guys I have a VIP on :23 with a 3-node pool bound to it. Each node listening on :23.



My question is this, outside of priority group activation, if all 3 servers are down, can the LTM send a service unavailable notification to the client?






7 Replies

  • It's a relatively simple iRule, but not such a simple question. Glad that works for you.



  • hoolio,



    real quick - this is basically balancing telnet. To return to the client "Service Down" will the above TCP respond suffice?
  • I'm not sure what a service down message looks like for telnet. If you need to use binary content in the TCP::respond command, you can follow the steps in SOL7875 and use the binary format command:



    sol7875: Certain data may contain values or characters within the ASCII range thar are not printable but need to be processed by an iRule before load balancing or other handling of the data can occur.




    binary format




  • Hamish's avatar
    Icon for Cirrocumulus rankCirrocumulus



    A 'standard' 'service down' message for telnet would be a tcp reset...




  • That's easy enough as LTM will send a reset if no pool members are available. No iRule needed.