Panasonic NN46240-710 - Manual (Page 99)

3 BGP/MPLS IP VPN troubleshooting
Nortel Secure Router 8000 Series
_________ Troubleshooting - VPN
Troubleshooting procedure
Step 1 Ensure the remote CE uses the Up private network addresses of the local PE. Using the
import-route direct command in the BGP VPN instance view on the local PE can ensure that
all the private network routes of the local PE can be advertised through MP-BGP. Replace the
ping -vpn-instance
vpn-instance-name dest-ip-address command with the ping -vpn-instance
vpn-instance-name -a source-ip-address dest-ip-address command.
—End
Summary
If you ping the remote CE network segment from PE, Nortel recommends that you specify the
source address of the ping packet.
3.3.5 Failure to establish the MP-EBGP peer in inter-AS
VPN-OptionC
Fault Symptom
Figure 3-8 Networking diagram of the inter-AS VPN-OptionC troubleshooting
PE1
i Backbone
^^^AS100
ASBR-PE1 ASBR- P E 2 f Backbone^^^
AS200 ^S*
•5i^
S2 o
y
PE2
As shown in Figure 3-8, when you configure the inter-AS VPN-OptionC, establishing the
MP-EBGP peer relationship between PE1 and PE2 fails. The PE1 and PE2 cannot ping through
the loopback address of each other.
After checking the routing table or the forwarding table, you find that multiple load-balancing
paths exist between PE2 and ASBR-PE2.
Fault analysis
In the inter-AS VPN-OptionC, PE learns the route of the peer PE through the Autonomous
System Boundary Router (ASBR) within the local AS.
After receiving the BGP public labeled route sent by the ASBR in the local AS, PE performs the
following action:
• The BGP module fills out the label and tunnel ID (Token in the routing table and FIB).
• The RM fills out the egress and iterative next hop of the route and FIB.
The BGP periodically searches if the LDP LSP to the local AS exists. If so, a new Next Hop
Label Forwarding Entry (NHLFE) is created and its Outgoing Token denotes the LDP LSP. The
tunnel ID of the new NHLFE is stored in the Token field of the routing table and FIB.
3-20 Nortel Networks Inc. Issue 5.3 (30 March2009)