1 2 3 4 Previous Next 49 Replies Latest reply: Apr 6, 2012 1:15 PM by gregsykes RSS

    OSPF route in BGP neighbor for R0 and R1 not showing


      We have a situation where the OSPF route for R0 and R1 is now showing for BGP..   Here's my first thought talking to my group member who has configured this in Packet Tracer.  I don't think Packet Tracer will support this. I could be wrong!  Please confirm if this is the case.  I am configuring this in GNS3 and will follow up with the final toplogy, but for now here is the file that was configured.



      OSPF route to BGP.PNG



      I have attached the pkt version 5.3.3.

        • 1. Re: OSPF route in BGP neighbor for R0 and R1 not showing
          Ronald Lopez

          If you can place the config for the routers we could have a better picture of it. I don't use packet tracer. In the mean time make sure that you are correctly redistributing the routes into the BGP process.

          • 2. Re: OSPF route in BGP neighbor for R0 and R1 not showing



            The routers are password protected. Can you remove password for easy access and discussion?



            • 3. Re: OSPF route in BGP neighbor for R0 and R1 not showing



              I was going to do this for you but I think you need th exposure on how to recovery a password on devices...


              Use this procedure:  It is very helpful espeacially out in the field..


              Do the password recovery if needed:

              [3/14/2012 9:36:31 PM] Gregory Sykes: [Wednesday, March 14, 2012 9:31 PM] Gregory Sykes:


              <<< Password Recovery

              The Password Recovery process is simple and takes about five minutes depending

              on how fast your router boots:

              1. Connect to the console port, start your terminal application, and power

              cycle the router. When you see the boot process beginning, hit the Break

              sequence. (This is usually Ctrl+Break, but it might differ for different terminal

              applications.) Doing this interrupts the boot process and drops the

              router into ROMMON.

              2. At the ROMMON prompt, enter the command confreg 0x2142 to set

              the configuration register to 0x2142.

              3. Restart the router by power cycling it or by issuing the command reset.

              4. When the router reloads, the configuration register setting of 0x2142

              instructs the router to ignore the startup-config file in NVRAM. You will

              be asked if you want to go through Setup mode because the router thinks

              it has no startup-configuration file. Exit from Setup mode.

              5. Press Return and enter the command enable to go into Privileged EXEC

              command mode. No password is required because the startup-config file

              was not loaded.

              6. Load the configuration manually by entering copy startup-config


              7. Go into the Global Configuration mode using the command configure

              terminal and change the password with the command enable password

              password or enable secret password.

              8. Save the new password by entering copy running-config startup-config.

              9. Go to the global config prompt, and change the configuration register

              back to the default setting with the command config-register 0x2102.

              Exit back to the Privileged EXEC prompt.

              10. Reboot the router using the reload command. You will be asked to save your

              changes; you can do so if you have made additional configuration changes.

              • 4. Re: OSPF route in BGP neighbor for R0 and R1 not showing

                What is this post about, router password recovery or a ospf-bgp route problem ?.


                A single post with the password would be shorter. I dont have packet tracer as many other people, so will not be able to understand and help in this question.


                If you could post your configurations and some show ip route, show bgp, etc, will be much easier to help you.




                • 5. Re: OSPF route in BGP neighbor for R0 and R1 not showing

                  I know how to do password recovery. I don't have 5mins to through away for that. I'm switching between 3 labs at a time and thought of taking at look at this one. If the lab was on password recovery then I wont have to ask you for it. If you are posting Lab for people to look into some other issues with it, why make them waste time to recovery passwaord. I guess that would be CCNA lab forum to do


                  Like Alex, this lab is not about password recovery.





                  • 6. Re: OSPF route in BGP neighbor for R0 and R1 not showing



                    Sorry for the inconvience, I removed the passwords from the configuration.. Here is the new pkt file.. Further looking this and Glory notified me that their in no configuration once the password reset is done everything is whiped.  Lets look at where this origniated from:AS Networks.PNG


                    Now looking at this configuration, you may create this in packet tracer or GNS3. It has been confirmed....We gave some brief history on BGP is our discussions which were as follows:


                    For those who don't know, "The Border Gateway Protocol (BGP)" is the protocol backing the core routing decisions on the Internet. It maintains a table of IP networks or 'prefixes' which designate network reach-ability among autonomous systems (AS). It is described as a path vector protocol. BGP does not use traditional Interior Gateway Protocol (IGP) metrics, but makes routing decisions based on path, network policies and/or rule-sets. For this reason, it is more appropriately termed a reach-ability protocol rather than routing protocol. This is all I know so far about this protocol. Maybe someone can shed some more light and enlighten the group and myself on more information about this.

                    • 7. Re: OSPF route in BGP neighbor for R0 and R1 not showing



                      Just looking at the heading "OSPF route in BGP neighbor for R0 and R1 not showing". I would have expected to see what was configured on each routers so be able to correct or point out where the problem is and why OSPF is not showing up. The aim of this post i supposed was to seeking assistance in identifying the problem(s) and make suggested solution(s). I would suggest you paste or attach your whole config  here so we can see what went wrong.

                      • 8. Re: OSPF route in BGP neighbor for R0 and R1 not showing

                        Hi Glory,


                        Yes I understand what your saying., Our group member Tassi created this configuration. Unfortunately, he placed passwords on each device in which we have no idea what those passwords are.. I thought by doing password recovery we would be able to see the problems with the model, but in retropspect it whiped the entire configuration. Like you, I would love to see what his intitial problem was, and I suggested that you speak with him in group when he is back online. So at this point, I decided to start from scatch, post the original configuration, and have either you the group or myself recreate the configuration as seen above. What were doing is proving at theory. If this model works on our end then we have validated that this configuration does work in  Packet Tracer. I'm skeptical that it does.  The goal now is to recreate the configuration, validate that it works in Packet Tracer, then create this in GNS3 to complete the assignment... My methods generally are trial and error... With very information it's almost impossible to guess what passwords were generated espeacially when there is no contact with the originator.... Let me know if you have any other questions?

                        • 9. Re: OSPF route in BGP neighbor for R0 and R1 not showing

                            But according to R5 configuration your problem is your bgp network command.


                            If you have two /24 networks, you cant propagate these into bgp with a bgp network The network command and mask under BGP is not like OSPF, this is not a wildcard, this not include everything inside the mask, the mask is an exact match.


                             You should have an igp route to that network and with that mask to properly propagate that prefix.


                             If you have two /24 interfaces, but want to propagate a /16 network, then you will have to configure an static router like the following :


                              ip route null 0


                             Or you will have to configure an aggregate route under bgp






                              For sure that with that configuration, if you execute a show ip bgp, you will not see the prefix. This is why you dont have an igp route to a network. The static route or the aggregate will get this.





                          • 10. Re: OSPF route in BGP neighbor for R0 and R1 not showing



                            Thanks for the input. Would it be possible for you to create a model for the group in Packet Tracer?

                            • 11. Re: OSPF route in BGP neighbor for R0 and R1 not showing

                                  Im sorry but dont have packet tracer. Anyway, if you have that topology and configuration under pt, configure the static route and this will work.




                              • 12. Re: OSPF route in BGP neighbor for R0 and R1 not showing

                                i got it working very well now all de route of ospf are now found in R0 which is running BGP , all de password is eddy

                                i di redistubution of ospf into bgp

                                • 13. Re: OSPF route in BGP neighbor for R0 and R1 not showing

                                  We are in the process of creating this in GNS3.  There was no pkt file posted from Edmond, in which I already have put a request in for.  Further anlaysis reveals that for this model, a BGP router will not advertise the routes specified in the network command unless it also has that route in its routing table. In this case, the network was added under the BGP process using the network command, but this route is not in the routing table. Only the more specific and routes are in the routing table as connected routes. By adding a static route to the null0 interface, the route will be in the IGP routing table and this route will be added to the BGP process and advertised to neighbors.

                                  • 14. Re: OSPF route in BGP neighbor for R0 and R1 not showing

                                      Hi Greg.


                                      The network behaviour is not scenario specific. This is the way the network command works. If you dont configure a netmask, then it uses the natural mask for that ip address, /8, /16, /24, if you specifiy a network mask, then will use that /22 or anything else.

                                      The network mask always match on a igp route. If you want to propagate anything else not in a igp route, then will have to use the aggregate, or redistribution into bgp.




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