Troubleshooting guide

8-7
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-01
Chapter 8 Troubleshooting Tag and MPLS Switching Connections
Initial Troubleshooting of Tag Switching
For detailed interface configuration information about tag switching, refer to the “Configuring Tag
Switching” chapter in the ATM Switch Router Software Configuration Guide.
Follow these steps to confirm the loopback interface 0 configuration on the switch router:
Step 1 Enter the show interfaces loopback 0 command to confirm the loopback interface 0 configuration on
the switch router.
AdminFl1Ls1# show interfaces loopback 0
Loopback0 is up, line protocol is up
Hardware is Loopback
Internet address is 2.2.2.2/24
MTU 1500 bytes, BW 8000000 Kbit, DLY 5000 usec, rely 255/255, load 1/255
Encapsulation LOOPBACK, loopback not set, keepalive set (10 sec)
Last input 00:00:03, output never, output hang never
Last clearing of “show interface” counters never
Queueing strategy: fifo
Output queue 0/0, 0 drops; input queue 0/75, 0 drops
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
73 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
AdminFl1Ls1#
Step 2 Check the Loopback 0 status field. It should be up.
Step 3 Check the line protocol field. It should be up.
Step 4 Check the Internet address field. It should display the IP address of the loopback interface on this switch
router.
For detailed information, refer to the “Configuring Tag Switching” chapter in the
ATM Switch Router Software Configuration Guide.