Cisco ONS 15454 SDH - Perform a Terminal Loopback on a Destination-Node Optical Port

1-58
Cisco ONS 15454 SDH Troubleshooting Guide, R5.0
July 2005
Chapter 1 General Troubleshooting
1.3.7 Perform a Terminal Loopback on a Destination-Node Optical Port
Test the Optical Card
Step 1 Complete the “Physically Replace a Traffic Card” procedure on page 2-271 for the suspected bad card
and replace it with a known-good one.
Caution Removing a card that currently carries traffic on one or more ports can cause a traffic hit. To avoid this,
perform an external switch if a switch has not already occurred. See the “2.10.2 Protection Switching,
Lock Initiation, and Clearing” section on page 2-260 for basic instructions. For detailed information,
refer to the Cisco ONS 15454 SDH Procedure Guide Chapter 15, “Maintain the Node.”
Step 2 Resend test traffic on the loopback circuit with a known-good card installed.
Step 3 If the test set indicates a good circuit, the problem is probably the defective card. Return the defective
card to Cisco through the RMA process. Log into the Cisco Technical Support Website at
http://www.cisco.com/techsupport for more information or log into
http://www.cisco.com/warp/public/687/Directory/DirTAC.shtml to obtain a directory of toll-free Cisco
TAC numbers for your country.
Step 4 Complete the “Physically Replace a Traffic Card” procedure on page 2-271 for the faulty card.
Step 5 Clear the facility (line) loopback on the port:
a. Click the Maintenance > Loopback > Port tabs.
b. Choose None from the Loopback Type column for the port being tested.
c. Choose the appropriate state (Unlocked; Locked,disabled; Unlocked,automaticInService) from the
Admin State column for the port being tested.
d. Click Apply.
e. Click Yes in the confirmation dialog box.
Step 6 Clear the facility loopback circuit:
a. Click the Circuits tab.
b. Choose the loopback circuit being tested.
c. Click Delete.
d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.
Step 7 Complete the “1.3.7 Perform a Terminal Loopback on a Destination-Node Optical Port” procedure on
page 1-58.
1.3.7 Perform a Terminal Loopback on a Destination-Node Optical Port
The terminal loopback at the destination-node port is the final local hardware error elimination in the
circuit troubleshooting process. If this test is completed successfully, you have verified that the circuit
is good up to the destination port. The example in Figure 1-27 shows a terminal loopback on an
intermediate-node destination STM-N port.