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Forum Replies

  1. Jason, you are exactly right. Suppose your ASBR is, and it has a default route in its RIB (it doesn’t matter whether that route came from EIGRP, or is a static route). From the ASBR, under your OSPF process, you would issue
    (config-router)#default-information originate

    Now, if you went to another OSPF router in the same area as the ASBR, you would see the following in its routing table:

    Gateway of last resort is to network
    O*E2 [110/1] via, 00:00:01, FastEthernet0/0

    So the ASBR is advertising an External Type-2

    ... Continue reading in our forum

  2. Hi rene
    I did " clear ip ospf process " after adding loopback ip .But my router ID did not change

    R1#clear ip ospf process
    Reset ALL OSPF processes? [no]: yes
    R1#show ip protocols
    *** IP Routing is NSF aware ***
    Routing Protocol is "ospf 1"
      Outgoing update filter list for all interfaces is not set
      Incoming update filter list for all interfaces is not set
      Router ID
      Number of areas in this router is 1. 1 normal 0 stub 0 nssa
      Maximum path: 4
      Routing for Networks: area 0
      Routing Information Sources:
    ... Continue reading in our forum

  3. Sims,
    When you add a loopback, OSPF won’t automatically change the router-id even if you clear the process. Since you have already created the OSPF instance, you will have to issue the command
    (config-router)#router-id <A.B.C.D>
    Where A.B.C.D is what you want the ID to become, and after that, clear the OSPF process.

    The other much more difficult option would be (once you already have your loopback created) to remove OSPF and add it back, via:

    (config)#no router ospf 1
    (config)#router ospf 1

    But you would have to re-enter your configuration parameters doing it

    ... Continue reading in our forum

  4. Hi Rene,
    i am trying to doing your LAB one by one…
    Based on below mention topic when i am trying to change router id automatically based on highest ip address on interface why its not changing after clear ip ospf process

    R2#sh version
    Cisco IOS Software, 7200 Software (C7200P-SPSERVICESK9-M), Version 12.4(15)T9, RELEASE SOFTWARE (fc5)
    Technical Support: http://www.cisco.com/techsupport
    Copyright (c) 1986-2009 by Cisco Systems, Inc.
    Compiled Tue 28-Apr-09 20:04 by prod_rel_team
    ROM: System Bootstrap, Version 12.4(12.2r)T, RELEASE SOFTWARE (fc1)
    BOOTLDR: Cisco 
    ... Continue reading in our forum

  5. Hello Arindom

    Indeed with the config as you have it set up, the router ID should become since it is the highest loopback ID. However, does remain the router ID even after the clear ip ospf process command.

    The only thing i can think of is that you have the router ID explicitly configured in the OSPF process as and this is why it is not changing. Please confirm that you have no configured router ID in the OSPF configuration.

    If all else fails, try rebooting the device. Let us know your results.

    I hope this has been helpful!


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