BETA DRAFT - CISCO CONFIDENTIAL
14-3
Cisco1800 Series Integrated Services Routers (Fixed) Software Configuration Guide
OL-6426-02
Chapter14 Troubleshooting
ATM Troubleshooting Commands
For details, see the “PortFast Configuration Error” section in the Spanning Tree Protocol Problems and
Related Design Considerations document.
ATM Troubleshooting Commands
Use the following commands to troubleshoot your ATM interface.
•ping atm interface Command
•show interface Command
•show atm interface Command
•debug atm Commands

ping atm interface Command

Use the ping atm interface command to determine whether a particular PVC is in use. The PVC does
not need to be configured on the router to use this command. Example 14-1 shows the use of this
command to determine whether PVC 8/35 is in use.
Example14-1 Determining If a PVC Is in Use
Router# ping atm interface atm 0 8 35 seg-loopback
Type escape sequence to abort.
Sending 5, 53-byte segment OAM echoes, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 148/148/148 ms
!----This command sends five OAM F5 loopback packets to the DSLAM (segment OAM packets).
If the PVC is configured at the DSLAM, the ping is successful.
!----To test whether the PVC is being used at the aggregator, enter the following command:
Router# ping atm interface atm 0 8 35 end-loopback
Type escape sequence to abort.
Sending 5, 53-byte end-to-end OAM echoes, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 400/401/404 ms
!----This command sends end-to-end OAM F5 packets, which are echoed back by the
aggregator.

show interface Command

Use the show interface command to display the status of all physical ports (Ethernet and ATM) and
logical interfaces on the router. Example14-2 shows sample command output.
Example 14-2 Viewing the Status of Selected Interfaces
Router# show interface atm 0
ATM0 is up, line protocol is up