Task 7.6 - Router Redundancy


Anyone knows what the effect will be if "ip irdp address 139.1.0.x" is not included in the config? Will the IRDP routers still send icmp messages that includes its own IP address as a possible default router for the clients?

Will configuring " ip irdp preference" to a high number on R3, without the ip irdp address statement on any router, meet the requirement of the task?




  • Hi,

    I ended up with similar config. If you enable debug ip icmp on you routers, you will see the sending and receiving of the irdp packets so it looks valid... On the other hand, I will probably end up always configuring the address manually from now on unless otherwise specified.

    For the hell of it, if you try to specify an address with a preference other than the interface's primary, you will notice that the routers starts sending 2 irdp advertisements per interval:

    one for the primary ip with a preference of 0

    one for the configured irdp address with the specified preference


  • Hi Barhar,

         As long as you configure the preference value, it will send. You can configure the preference with command "ip preference <value>" or with command "ip address x.x.x.x <value>". The second option would normally be used if you want the router to send advertisements for another IP address than its own configured one.

     Yes, by setting it only on R3 will meet the requierments; still, for configuration consistency, th SG modifies the values on all routers.


Sign In or Register to comment.