Troubleshooting guide

13-30
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-01
Chapter 13 Troubleshooting ATM Router Module Connections
Troubleshooting OAM on ATM Router Module Connections
The system error message “%LINEPROTO-5-UPDOWN: Line protocol on Interface ATM0/0/0.5,
changed state to down” indicates the subinterface ATM 0/0/0.5 has changed status to down because the
PCV was disabled on switch router c8540-2.
Step 12 At router c7576-1, use the show atm traffic command to check the OAM cells received and sent.
c7576-1# show atm traffic
.
(Information Deleted)
.
442 OAM cells received
708 OAM cells sent
Step 13 At router c7576-1, use the show atm traffic command a second time, and check the number of OAM
cells received and sent.
c7576-1# show atm traffic
.
(Information Deleted)
.
442 OAM cells received
734 OAM cells sent
Step 14 Check the number before the OAM cells received field. Since the number of OAM cells received has not
incremented since the previous display, this confirms the connection is down and the OAM cells are sent
but not received.
Step 15 At router c8540-1, use the show atm vc interfaces atm command with the VPI and VCI parameters to
confirm the ATM router module subinterface OAM status and configuration.
c8540-1# show atm vc interfaces atm 10/0/1.5 2 105
Interface: ATM10/0/1, Type: arm_port
VPI = 2 VCI = 105
Status: UP
Time-since-last-status-change: 00:43:05
Cross-connect OAM-configuration: End-to-end-loopback-on
Cross-connect OAM-state: OAM-Up End-to-end-loopback-failed
OAM-Loopback-Tx-Interval: 5
Step 16 Check the Status field. It should be UP.
Step 17 Check the Time-since-last-status-change field. It should indicate the time since you enabled OAM on the
subinterface.
Step 18 Check the Cross-connect OAM-configuration field. It should indicate End-to-end-loopback-on.
Step 19 Check the Cross-connect OAM-state field. It should indicate OAM-Up, but that the
End-to-end-loopback-failed because the PCV was disabled on switch router c8540-2.
The effect of OAM failure on an interface or subinterface is as follows:
• On the ATM router module the interface or subinterface status and VC remain UP, causing the
following:
– the VC remains in switch fabric
– OAM loopback cells are still sent, but not received