2 Replies Latest reply on Jan 9, 2014 10:45 AM by noor

    OSPF unstable adjacency on MLPPP to Cisco IOS XR router

    curtismo New Member

      Attempting to connect to a large telecom vendor's MPLS network using MLPPP over 2 T1s and OSPF routing protocol with our Adtran 3450 running AOS R10.6.0.  Previous non-Cisco, non-Adtran router works perfectly; replacement with Adtran 3450 experiences loss of adjacency over MLPPP link to vendor's Cisco IOS XR-based router at random timings from 2 to 8 minutes.  MPLS vendor says dead timer is timing out.  Adtran "debug ip ospf" shows link drops from FULL to INIT to EXSTART to FULL adjacency. Dropping down to one T1 active and OSPF will stay stable.  Vendor requires PPP fragmentation to be disabled, which appears to be the default for AOS.  MTU on the MLPPP is set for default of 1500.

       

      After working up from Tier 1 support at large vendor, got to Tier 3.  I let them know that I had another Adtran 3450 running MLPPP with two T1s and OSPF with no adjacency issues, and has been running that way for a year.  In reviewing, the engineer found the working Adtran was interfaced with a Juniper M320 router platform.

       

      The vendor then moved the MLPPP connection from the Cisco IOS XR platform to the Juniper platform, which resolved the issue.

       

      It appears that there are serious Cisco IOS XR interoperability issues with MLPPP and Adtran Netvanta routers.  Not sure, but in another similar case the vendor said they are running Cisco IOS XR v 3.8.2.

        • Re: OSPF unstable adjacency on MLPPP to Cisco IOS XR router
          levi Employee

          curtismo:

           

          Thank you for asking this question in the support community.  I see you opened a ticket with ADTRAN Technical Support on this issue.  Were you able to obtain the debug ppp negotiation or debug ip ospf output when you were experiencing the issue when connected to the Cisco?

           

          Levi

            • Re: OSPF unstable adjacency on MLPPP to Cisco IOS XR router
              Employee

              curtismo -

              I went ahead and flagged this post as "Assumed Answered". If any of the responses on this thread assisted you, please mark them as Correct or Helpful as the case may be with the applicable buttons. This will make them visible and help other members of the community find solutions more easily. If you have any additional information on this that others may benefit from, please come back to this post to provide an update. If you still need assistance, we would be more than happy to continue working with you on this - just let us know in a reply.

               

              Thanks,

              Noor