Local Tunnel Interface Fails to Ping the Remote Tunnel Interface Although Their
Network Protocol Status Is Up
Fault Symptom
Figure 12-3
Networking between local and remote tunnel interfaces
RouterA
Tunnel0/0/1
11.1.1.1/24
Tunnel0/0/1
21.1.1.1/24
GRE Tunnel
RouterB
Loopback1
2.2.2.2/32
Loopback1
1.1.1.1/32
network
The network layer protocol is Up on Tunnel0/0/1 of RouterA and Tunnel0/0/1 of RouterB, but
the two interfaces cannot ping each other.
Fault Analysis
Possible causes are as follows:
l
GRE key configurations of the two interfaces are inconsistent.
l
IP addresses of the two interfaces are on different network segments and no reachable routes
exist between the two ends.
Run the
display interface tunnel
interface-number
command on the two tunnel interfaces to
check whether their GRE key configurations are consistent.
<RouterA>
display interface tunnel 0/0/1
Tunnel0/0/1 current state : UP
Line protocol current state : UP
Last line protocol up time : 2011-03-08 16:58:30
Description:HUAWEI, AR Series, Tunnel0/0/1 Interface
Route Port,The Maximum Transmit Unit is 1500
Internet Address is 11.1.1.1/24
Encapsulation is TUNNEL, loopback not set
Tunnel source 1.1.1.1 (LoopBack1), destination 2.2.2.2
Tunnel protocol/transport GRE/IP, key 2
keepalive disabled
Checksumming of packets disabled
......
<RouterB>
display interface tunnel 0/0/1
Tunnel0/0/1 current state : UP
Line protocol current state : UP
Last line protocol up time : 2011-03-08 16:43:57
Description:HUAWEI, AR Series, Tunnel0/0/1 Interface
Route Port,The Maximum Transmit Unit is 1500
Internet Address is 21.1.1.1/24
Encapsulation is TUNNEL, loopback not set
Tunnel source 2.2.2.2 (LoopBack1), destination 1.1.1.1
Tunnel protocol/transport GRE/IP, key disabled
keepalive disabled
Huawei AR2200-S Series Enterprise Routers
Troubleshooting
12 VPN
Issue 01 (2012-01-06)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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