Cisco ONS 15454 SDH - Troubleshooting MXP, TXP, or FC_MR Circuit Paths With Loopbacks

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Cisco ONS 15454 SDH Troubleshooting Guide, R5.0
July 2005
Chapter 1 General Troubleshooting
1.5 Troubleshooting MXP, TXP, or FC_MR Circuit Paths With Loopbacks
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.
Step 3 If the test set indicates a good circuit, the problem was 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 defective card.
Step 5 Clear the terminal loopback on the port:
a. Double-click the source-node card with the terminal loopback.
b. Click the Maintenance > Loopback tab.
c. Select None from the Loopback Type column for the port being tested.
d. Select the appropriate state (Unlocked; Locked,disabled; Unlocked,automaticInService) in the
Admin State column for the port being tested.
e. Click Apply.
f. Click Yes in the confirmation dialog box.
Step 6 Clear the terminal 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.
The entire circuit path has now passed its comprehensive series of loopback tests. This circuit qualifies
to carry live traffic.
1.5 Troubleshooting MXP, TXP, or FC_MR Circuit Paths With
Loopbacks
The MXP, TXP, and FC_MR loopback test for circuit path failure differs from electrical, optical, and
Ethernet testing in that loopback testing does not require circuit creation. MXP, TXP, and FC_MR client
ports are statically mapped to the trunk ports so no signal needs to traverse the cross-connect card (in a
circuit) to test the loopback.