mpls & ospf

[flyjunli]

when i design mpls vpn ,can i use multi area in global igp routing design. is there any problem in TE or mpls vpn

i saw many design just use one area 0 for global igp

Thank you!

[swaroop.potdar]

Yes its supported, but you cannot configure dynamic inter-area TE tunnels. you have to reply on the explicit path option. To sumarize its more like manually connecting the ABR's and between the ABR's they decide in their own area how to reach the next ABR.

Here is a link explaning the details with config.

http://www.cisco.com/en/US/tech/tk436/tk832/tech_brief09186a00801f0b2d.html

But its only for simulation purposes. If there is no real constraint single area is good for now.

HTH-Cheers,

Swaroop

[flyjunli]

Hi,

Thank you!

there are 150 routers including 7609,7604,customer want to use multiple area.

we have to implement mpls vpn, may be TE,multicast in the future.

i want to use sing area 0, but customer ask to use multiple area.

if we just use mpls vpn, is there any problem for multiple areas.

thank you!

[mheusing · Accepted solution]

Hi,

As long as you have host routes in all routers for all BGP next hops, i.e. PE loopbacks, there is no problem. MPLS really does not care how a route is inserted into the RIB and has no knowledge about routing topology.

So as long as you only use MPLS L3VPN and do not summarize the loopback networks you are fine.

Just as a side note: in general 150 routers of type 7600 in a single area should not pose a problem. The 7600 have enough memory and cpu power to deal with that. Of course there might be other reasons I do not know of leading to a multi-area design.

Hope this helps! Please rate all posts.

Regards, Martin