Re: OSPF Sham Links?

OK. So obviously it is getting into BGP somehow.

Are you sure you are not redist connected or something

------Original Message------
From: Group Study
To: Joe Astorino
Cc: CCIE Groupstudy
Subject: Re: OSPF Sham Links?
Sent: Mar 23, 2010 7:11 PM

Joe,

I saw this link too... The funny thing is, I'm not advertising the
Loopbacks for the Sham link anywhere... It's just in a vrf, I didn't
specify the network for the loopbacks under ospf nor did I advertise
it in BGP....

Weird...

Any thoughts on R3 knows of R4s loopback for the sham link? It shows
up as an iBGP route in the vrf routing table... but I don't know how
it got there...

On Tue, Mar 23, 2010 at 7:01 PM, Joe Astorino <jastorino_at_ipexpert.com> wrote:
> HI!
>
> I believe the way that is supposed to work is that you advertise your
> newly created loopbacks into BGP. Please see the following link:
>
> http://www.cisco.com/en/US/docs/ios/12_2t/12_2t8/feature/guide/ospfshmk.html#wp1035280
>
>
>
> On Tue, Mar 23, 2010 at 6:47 PM, Group Study <gs_at_netengineer.org> wrote:
>> I'm doing an MPLS lab on OSPF Sham links and I'm a bit confused.
>>
>> On my two PEs, R3 and R4, I create a loopback each and then put them
>> into a VRF but I'm not putting these interfaces or host subnets into a
>> routing protocol. R3 and R4 have 2 P routers in between them that are
>> speaking ISIS as the IGP and R3 and R4 are MP-BGP (iBGP) peers. R3 is
>> also connected SW2 (CE) and R4 is connected to R6 (CE) and they have a
>> backdoor link connected to each other. The CE-PE protocol is OSPF.
>>
>> How does R3 know about the Loopback of R4, the destination of the OSPF
>> Sham link and vice versa?
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
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>>
>>
>>
>>
>>
>
>
>
> --
> Regards,
>
>
>
> Joe Astorino - CCIE #24347 (Earned not bought)
> Sr. Technical Instructor - IPexpert
> Mailto: jastorino_at_ipexpert.com
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Sent from my Verizon Wireless BlackBerry

Regards,

Joe Astorino - CCIE #24347 (Earned not bought)
Sr. Technical Instructor - IPexpert
Mailto: jastorino_at_ipexpert.com
Telephone: +1.810.326.1444
Live Assistance, Please visit: www.ipexpert.com/chat
eFax: +1.810.454.0130

IPexpert is a premier provider of Self-Study Workbooks, Video on Demand, Audio Tools, Online Hardware Rental and Classroom Training for the Cisco CCIE (R&S, Voice, Security & Service Provider) certification(s) with training locations throughout the United States, Europe, South Asia and Australia. Be sure to visit our online communities at www.ipexpert.com/communities and our public website at www.ipexpert.com

Blogs and organic groups at http://www.ccie.net
Received on Tue Mar 23 2010 - 23:37:00 ART