Specifications

2-10
Cisco ONS 15454 Troubleshooting and Maintenance Guide
November 2001
Chapter 2 General Troubleshooting
b. Resend test set traffic on the loopback circuit.
c. If the signal received by the test set is still faulty or non-existent, return the defective card to Cisco.
Call the Technical Assistance Center (TAC) at 1-877-323-7368 to open an RMA case.
Step 21 If the circuit is now good, the cross-connect card may have had a temporary problem that was cleared
by the side switch.
Step 22 Replace the defective cross-connect card.
Step 23 Click the Circuits tab.
Step 24 Highlight the newly-created hairpin circuit and click Delete.
Step 25 Proceed to the “Perform a Hairpin on a Destination Node” procedure on page 2-10.
Procedure: Perform a Hairpin on a Destination Node
The third test is a hairpin circuit on the cross-connect card in the destination node. To perform this test,
you must also create a bidirectional circuit from the source DS-N card to the source OC-N node in the
transmit direction. Creating the bidirectional circuit and completing a successful hairpin eliminates the
possibility that the source and destination OC-N cards, the source and destination cross-connect card, or
the fiber span is responsible for the faulty circuit.
Figure 2-7 Hairpin on a destination node
Step 1 Test the test set with a hard loop if you have not done so.
Note To perform a hard loop, bridge the test set transmit (Tx) and receive (Rx) terminals with an
appropriate cable and send traffic across this loop to ensure the test set works.
Step 2 If you are starting the current procedure with the electrical test set hooked up to the DS-N card, leave
the test set hooked up.
Step 3 If you are starting the current procedure without the electrical test set hooked up to the DS-N card, use
appropriate cabling to attach the electrical test set transmit (Tx) and receive (Rx) terminals to the EIA
connectors or DSx panel for the port you are testing. Both transmit (Tx) and receive (Rx) connect to the
same port. Set up the test set accordingly.
Step 4 To create the first circuit, click the Circuits tab and click the Create button.
Step 5 Give the circuit an easily-identifiable name, such as bidirectional1.
Step 6 Select the appropriate circuit type, VT or STS-1.
Hairpin
Bidirectional
circuit
Unidirectional
circuit
DS-N OC-N
XC
ONS 15454
Source
OC-N DS-N
XC
ONS 15454
Destination
DS-N
DS-N
Slot 6
Slot 12
Slot 12
Slot 6
Test Set A
OC-N
55264