MPLS TE Inter Area question

Trying to configure mpls te on both isis and ospf.

When in ISIS, i configure a tunnel, where head end router is in L1 and the tail end router is in L2, the tunnel comes up and even though i am using autoroute announce, traffic doesnt traverse over the tunnel. If however i put in a static route on the head end, only then, the traffic flows to it destination via the tunnel. Same story with OSPF.

I got the statment below from Cisco's doc

You can configure multiple areas within an IS-IS Level 1. This is transparent to TE. TE has topology information about the IS-IS level, but not the area ID.

I assummed that if traffic comes from L1 and the TE tunnel head end is in L1 domain and the tunnel traverses through L1 --L2--L1 (regardless of area) then this particular sceanrio would work (which works).

So the question is, is my interpretation correct or am i missing something? Also, same thing is happening in OSPF, topology below,

R7-------------R3-------------R2---------------R5

         Area 1         Area 0            Area 2

If tunnel starts from R7 towards R5, tunnel comes up but traffic is not mapped to the tunnel until i use a static (autoroute annouce didnt work)

 

typical config

L1 or Area 1

mpls traffic-eng router-id0

mpls traffic-eng level-1 (area 1)

 

L2 or area 0

mpls traffic-eng router-id0

mpls traffic-eng level-1 (area 1)

mpls traffic-eng level-2 (area 0)

 

Any thoughts, why do i need a static route to make this work (especially in OSPF if i want inter-area TE)?

 

 

 

 

 

Comments

Sign In or Register to comment.