Hello,

I am running an inter-as + CSC scenario with OSPF and MPLS between the SPs.
The LDP peering is dropping exactly every 3 minutes and coming back up.
Connectivity is fine throughout the VPN when the session is up. I don't see
any route flapping in the debugs.

AS65123[R3]---------[R8]AS100---------AS200[R9]---------[R1]AS65123

AS100 and AS200 have an inter-as VPN supporting the 2nd level carrier
AS65123.
R9 and R8 have vrf interfaces connected to R1 and R3 respectively.
R1 has an LDP/OSPF peering with R9 (in the vrf) in AS100
R3 has an LDP/OSPF peering with R8 (in the vrf) in AS200

Both LDP sessions are bouncing on queue every 3 minutes! Here is R8 for
example:

R8#
*Sep  3 21:50:49.575: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.3:0 is DOWN
*Sep  3 21:50:59.475: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.3:0 is UP
*Sep  3 21:53:59.491: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.3:0 is DOWN
*Sep  3 21:54:09.291: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.3:0 is UP
*Sep  3 21:57:09.311: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.3:0 is DOWN
*Sep  3 21:57:19.331: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.3:0 is UP
*Sep  3 22:00:19.351: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.3:0 is DOWN
*Sep  3 22:00:29.239: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.3:0 is UP

Now just before the session dies I get the following from "debug mpls ldp
transport events interface x/x". This is from R9:

R9#
*Sep  3 22:09:27.295: ldp: Send ldp hello; Serial1/2, src/dst
123.1.9.9/224.0.0.2, inst_id 0
*Sep  3 22:09:28.787: ldp: Rcvd ldp hello; Serial1/2, from 123.1.9.1 (
123.123.123.1:0), intf_id 0, opt 0xC
*Sep  3 22:09:32.127: ldp: Send ldp hello; Serial1/2, src/dst
123.1.9.9/224.0.0.2, inst_id 0
*Sep  3 22:09:33.239: ldp: Rcvd ldp hello; Serial1/2, from 123.1.9.1 (
123.123.123.1:0), intf_id 0, opt 0xC
*Sep  3 22:09:36.111: ldp: Send ldp hello; Serial1/2, src/dst
123.1.9.9/224.0.0.2, inst_id 0
*Sep  3 22:09:36.907: tagcon: Session KeepAlive timer expired, peer
123.123.123.1:0 (pp 0x64027BD8)
*Sep  3 22:09:36.911: ldp: Close LDP transport conn for adj 0x63486648
*Sep  3 22:09:36.915: ldp: Closing ldp conn 123.1.9.9:646 <->
123.123.123.1:11015, adj 0x63486648
*Sep  3 22:09:36.919: ldp: Adj 0x63486648; state set to closed
*Sep  3 22:09:36.923: %LDP-5-NBRCHG: LDP Neighbor 123.123.123.1:0 is DOWN

Even though I am sending and receiving hellos, I am getting the session
keepalive timer expired. Any ideas?

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

Reply via email to