Troubleshooting guide

5-10
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-02
Chapter 5 Troubleshooting Switch Router ATM Interface Connections
Performing OAM Loopback Tests
Configuring Loopback Examples
The following examples show how to perform loopback tests on the interfaces shown in Figure 5-3.
If users connected to the Fast Ethernet Catalyst 5000 switch in the manufacturing building are not able
to connect to the other users outside their building (including the DNS server in the administration
building), you should try a loopback test. Use the procedures described in this section to test the
ATM switch router connections starting at the middle section and proceeding outward.
Figure 5-3 Loopback Test Configuration Example
Use the atm ping command to confirm the ATM connection between the administration and
manufacturing buildings.
Perform the interface loopback tests in the following order:
Test 1—Segment network-side loopback between ATM switch router AdminFl1Ls1, interface 1/0/0, and
ATM switch router ManuFl1Ls1, interface 4/0/1
Test 2—Segment link-side loopback between the DNS server and ATM switch router AdminFl1Ls1,
interface 4/0/0
Test 3—End-to-end loopback between the DNS server and the Catalyst 5000 Fast Ethernet switch,
ManuFl1CaS1, interface 1/1
Manufacturing building
Administration building
E-mail and meeting
database servers
DNS server
PVC
(AdminFl1GW)
(AdminFl1Ls1)
(ManuFl1CaS1)
(ManuFl1Ls1)
4/0/1
1/0/0
PNNI
Test 3
Test 1
Test 2
1/1
4/0/0
0/1/0
10294
Command Purpose
ping atm interface atm card/subcard/port vpi [vci]
[atm-prefix prefix] | [end-loopback] |
[ip-address ip-address] | [seg-loopback]}
Checks the interface connection.