RE: MPLS and OSPF Area 0 Hierarchy

Couple other interesting scenarios to consider:

PE - area1 - CE - area0
Area 0 routes will not appear on PE, because CE, ABR, will set down-bit on
the IA Type 3 OSPF routes and PE will reject them because of loop prevention
check. You can configure "capability vrf-lite" on the PE to disable loop
prevention check. You will then see those routes on the PE. Keep in mind
that some of the routes will become external.

PE - area1 - CE1
   \_ area2 - CE2
CE1 will not see CE2 routes because you are missing OSPF Area 0. The
solution is to create a VRF loopback on PE and put it into area0.

Regards,

Roman Rodichev
6xCCIE #7927 (R&S, Security, Voice, Storage, Service Provider, Wireless)
Instructor, Content Developer
ieMentor Corporation http://www.iementor.com
Y!M: roman7927

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Muhammad Anser Khan
Sent: Monday, February 08, 2010 7:51 AM
To: Syed Khalid Ali
Cc: Cisco Group
Subject: Re: MPLS and OSPF Area 0 Hierarchy

Dear Syed,

I dont think so that two different areas will communicate through MPLS
SuperBackbone Area 0. This Superbackbone Area has different meaning compared
to DMVPN.

Following are the scenarios are possible from CE :

Area 0 to Area 0
Area 0 to Area 1
Area 1 to Area 1

Sham links usually used when we have backdoor links for the same area.

This MPLS SuperBackbone Area 0 used for "Internal OSPF Routes Across MPLS
VPN Backbone" with the help of BGP Extended Communities for OSPF.

Regards,
Anser

On Fri, Feb 5, 2010 at 6:53 PM, Syed Khalid Ali
<khalid_khursheed_at_hotmail.com> wrote:
> Group:
> I need clarification on how area 0 is maintained across MPLS networks
between customer network. Some of the example I am going through right now
are something like this:
> CE1(OSPF A1)--(PE1)--P1---P2--CE2(OSPF A2)
>
> OSPF (in area 0) is running on SP network (only). Now in a typical DMVPN
environment, Area 0 is maintained across the WAN for each site of the
customer.Area_1--site_1---Area_0---site_2--Area_2.
> How does it related to this Area 0 concepts?
>
> ThanksKhalid
>
>
> _________________________________________________________________
> Hotmail: Free, trusted and rich email service.
> https://signup.live.com/signup.aspx?id=60969
>
>
> Blogs and organic groups at http://www.ccie.net
>
> ______________________________________________________________________
> _ Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html

Blogs and organic groups at http://www.ccie.net
Received on Tue Feb 09 2010 - 01:07:48 ART