Thank you to all for the support and responses. I took a different approach and asked myself "is this the best use of bgp backdoor?" and the answer is no. BGP backdoor is used when you want to increase the AD of a BGP learned route in favor of an OSPF learned route, for example. It is not good to use in this case as it would once again cause instability when the ospf learned route is lost, as Joe mentioned. I believe it would be best to remove the network statement in BGP in this particular case, as it is still learned through ospf and redistributed back into BGP at another point in the network. Thanks again for the feedback. Nick
________________________________ From: Joe Sanchez <[email protected]> To: Nick Bonifacio <[email protected]> Cc: Marko Milivojevic <[email protected]>; "[email protected]" <[email protected]> Sent: Friday, September 14, 2012 7:56 PM Subject: Re: [OSL | CCIE_RS] Lab 3-1 Troubleshooting Ticket 5 Nick, believe me... I understand, I have the same Best Friend and getting through the lab exam in time is very tough for me because I psychoanalys everything. Regards, Joe Sanchez ( please excuse the brevity of this email as it was sent via a mobile device. Please excuse misspelled words or sentence structure.) On Sep 14, 2012, at 12:48 PM, Nick Bonifacio <[email protected]> wrote: > But best practice is out the window in the lab, right? > > Are we both correct and satisfy the task? > > Sorry, but I have this friend and his initials are O.C.D. > > > Sent from my iPhone > > On Sep 14, 2012, at 1:40 PM, Marko Milivojevic <[email protected]> wrote: > >> I like what I read. I like it very much :-) >> >> -- >> Marko Milivojevic - CCIE #18427 (SP R&S) >> Senior CCIE Instructor - IPexpert >> >> On Fri, Sep 14, 2012 at 8:29 AM, Joe Sanchez <[email protected]> wrote: >>> Nick, when I did this lab I thought the same thing, but after looking at >>> the idea of using some other method of learning the lo0 via BGP and an IGP >>> I thought about how would the backdoor command come into play; which it >>> would never help because if you loose the IGP route and the 1.1.1.1 was >>> populated into the BGP table, we would drop the connection anyways, >>> therefore removing the network statement from R1 was the only logical >>> answer I could come up with. In this particular case there is a single >>> connection with two peers from R1s perspective. >>> >>> Regards, >>> Joe Sanchez >>> >>> ( please excuse the brevity of this email as it was sent via a mobile >>> device. Please excuse misspelled words or sentence structure.) >>> >>> On Sep 14, 2012, at 8:03 AM, Nick Bonifacio <[email protected]> wrote: >>> >>>> Spoiler alert: Do not read ahead if you have not done this lab/question >>>> yet! >>>> >>>> >>>> Ticket 5 is as follows: >>>> "The BGP peering between R1 and R2/R4 is flapping and needs to be >>>> stabilized. Please correct the problem." >>>> >>>> >>>> From my first look at R2 and R4, it appears that they are learning about >>>> 1.1.1.1 (update source) through BGP which would of course cause problems. >>>> The solution is to remove network 1.1.1.1 mask 255.255.255.255 from router >>>> 1, but to me this seems like it would go against "keep the spirit of the >>>> config". >>>> >>>> What I did on R2 and R4: >>>> >>>> >>>> router bgp 2456 >>>> network 1.1.1.1 mask 255.255.255.255 backdoor >>>> >>>> This makes the preferred route to 1.1.1.1 over OSPF instead of BGP by >>>> making the distance of the 1.1.1.1 route 200 and keeps the config intact. >>>> >>>> Is this a better/worse solution? Do I not understand the function of the >>>> BGP backdoor? >>>> >>>> thanks, >>>> Nick >>>> _______________________________________________ >>>> For more information regarding industry leading CCIE Lab training, please >>>> visit http://www.ipexpert.com/ >>>> >>>> Are you a CCNP or CCIE and looking for a job? Check out >>>> http://www.platinumplacement.com/ >>>> >>>> http://onlinestudylist.com/mailman/listinfo/ccie_rs >>> _______________________________________________ >>> For more information regarding industry leading CCIE Lab training, please >>> visit www.ipexpert.com >>> >>> Are you a CCNP or CCIE and looking for a job? Check out >>> www.PlatinumPlacement.com >>> >>> http://onlinestudylist.com/mailman/listinfo/ccie_rs _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com http://onlinestudylist.com/mailman/listinfo/ccie_rs
