Panasonic NN46240-710 - Manual (Page 64)

2 GRE troubleshooting
Nortel Secure Router 8000 Series
_________ Troubleshooting - VPN
127. 0.0.1/32 127. 0.0.1 HU t 0] InLoop0 0x0
127. 0.0.0/8 127. 0.0.1 U t 0] InLoop0 0x0
100. 2.1.2/32 127. 0.0.1 HU t 0] InLoop0 0x0
100. 2.1.0/24 100. 2.1. 2 U t 0] Pos1/0/0 0x0
10.2 .1.2/32 127. 0.0.1 HU t 0] InLoop0 0x0
10.2 .1.0/24 10.2 .1.2 U t 0] Pos2/0/0 0x0
30.1 .1.2/32 127. 0.0.1 HU t 0] InLoop0 0x0
30.1 .1.0/24 30.1 .1.2 U t 0] Tun1/0/0 0x0
The preceding FIB shows that Nortel 1 has no route to Nortel 2 on the network segment
100.2.1.0; Nortel 2 has no route to Nortel 1 on the network segment 100.1.1.0. Therefore, the
status of the tunnel interface at both ends is down, and the two ends cannot ping each other.
Configure a static route or dynamic routing protocol on Nortel 1 and Nortel 2 respectively.
Then, Nortel 1 has routes from 100.1.1.0 to 100.2.1.0; Nortel 2 has routes from 100.2.1.0 to
100.1.1.0.
—End
If the network layer protocol is still down, contact Nortel technical personnel.
If the network layer protocol on both ends of the tunnel interface changes to up but the ping of
the peer tunnel fails, perform the troubleshooting steps in the following section.
Network layer protocols on both ends of the tunnel interface are up
Step 1 Check that the configurations of the GRE keys on both ends are consistent.
Use the display interface tunnel interface-number command on both ends to check that the
GRE keys are consistent.
The correct configuration is one of the following two situations:
• No GRE key is configured on either end.
• The same key-number is configured on both ends.
If the configuration is correct but the two ends cannot ping through each other, perform as
follows.
Step 2 Check that reachable routes exist between the tunnel interfaces.
After you complete the previous step, the tunnel status at both ends is up and the physical
interface can ping through each other. But you cannot ping the tunnel interface successfully.
Check whether the IP addresses of the tunnel interfaces on both ends are on the same network
segment; if not, configure routes to the IP address of the remote tunnel interface.
—End
If the GRE tunnel fault persists, contact Nortel technical personnel.
2.3 Troubleshooting cases
This section provides the following troubleshooting cases:
• Ping of the peer tunnel fails although the network layer protocols on both ends are up
2-10 Nortel Networks Inc. Issue 5.3 (30 March2009)