Are you sure that the IGP was converged before the tunnels tried to
start determining their path.
I can imagine that when RSVP tells the tunnel that everything is fine
and IGP is not fully converged this would happen.
Try loading those configs again, but with the tunnels shutdown. Then
no shut them as the IGP is converged.
I told this a few times, but MPLS features like TE and CsC can be a
bit buggy in IOS 12.2S (12.0S is way better) and not function 100%. So
the order in which you enter the commands can be important as
processes can hang sometimes if you don't do it in the right way :-)
--
Regards,
Rick Mur
CCIE2 #21946 (R&S / Service Provider)
Sr. Support Engineer – IPexpert, Inc.
URL: http://www.IPexpert.com
On 20 sep 2009, at 15:46, Bryan Bartik wrote:
Hello,
I was troubleshooting an MPLS inter-area tunnel that was working
fine yesterday. I loaded my saved configs this morning and the
tunnels were down. The topology is as follows:
R7---R6 = area 876
R7---R8 = area 876
R8---R6 = area 0
Basically a full mesh of 3 routers with the R6/R8 link in area 0. R6/
R8 loopbacks are in area 0 as well. There is an explicit tunnel from
R7 that goes through R6 on towards R8. The tunnel is configured with
an explicit path:
R7#sho run int tun 78
interface Tunnel78
ip unnumbered Loopback0
tunnel destination 6.7.8.8
tunnel mode mpls traffic-eng
tunnel mpls traffic-eng path-option 1 explicit name R7-R8
R7#sho ip explicit-paths
PATH R7-R8 (loose source route, path complete, generation 4)
1: next-address 192.168.76.6 <---R7/R6 link in area 876
2: next-address loose 192.168.86.8 <---R6/R8 link in area 0
During troubleshooting I noticed the TE metric was listed as invalid
in "sho mpls traffic-eng topology"
IGP Id: 6.7.8.7, MPLS TE Id:6.7.8.7 Router Node (ospf 1 area 876)
link[0]: Point-to-Point, Nbr IGP Id: 6.7.8.6, nbr_node_id:2,
gen:3
frag_id 0, Intf Address:192.168.76.7, Nbr Intf Address:
192.168.76.6
TE metric:invalid, IGP metric:10, attribute flags:0x0
physical_bw: 100000 (kbps), max_reservable_bw_global:
75000 (kbps)
max_reservable_bw_sub: 0 (kbps)
So I change the path-selection method to IGP and the path came up.
R7(config)#int tun 78
R7(config-if)#tunnel mpls traffic-eng path-selection metric igp
01:28:06: %LINEPROTO-5-UPDOWN: Line protocol on Interface Tunnel78,
changed state to up
I can't find much information about why the TE metric was invalid,
and I never ran into this before. So I switched the path-selection
metric back to te and the tunnel stayed up, even after shutting/no
shutting.
My question is: What gives? Why is the TE metric listed as invalid?
And why did switching the path-selection method to igp make the
tunnel come up but switching it back not make it go down?
Thanks,
--
Bryan Bartik
CCIE #23707 (R&S), CCNP
Sr. Support Engineer - IPexpert, Inc.
URL: http://www.IPexpert.com
_______________________________________________
For more information regarding industry leading CCIE Lab training,
please visit www.ipexpert.com
_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit
www.ipexpert.com
