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Cisco ONS 15310-CL and Cisco ONS 15310-MA Troubleshooting Guide, R7.0
78-17235-01
Chapter 1 General Troubleshooting
1.2.4 Perform a Hairpin Test on a Destination-Node Port
Test the Terminal Loopback Circuit on the Destination-Node Port
Step 1
If the test set is not already sending traffic, send test-set traffic on the loopback circuit.
Step 2
Examine the test traffic being received by the test set. Look for errors or any other signal information
that the test set is capable of indicating.
Step 3
If the test set indicates a good circuit, no further testing is necessary on the loopback circuit. Clear the
terminal loopback:
a.
Double-click the 15310-CL-CTX or CTX2500 in the destination node with the terminal loopback.
b.
Double-click the appropriate card containing the electrical circuit you are testing, and click the
appropriate tab:
•
Maintenance > DS1 > Loopback
•
Maintenance > DS3 > Loopback
•
Maintenance > EC1 > Loopback
c.
Select
None
from the Loopback Type column for the port being tested.
d.
Select the appropriate state (IS,AINS,AINS OOS,DSBLD or OOS,MT) in the Admin State column
for the port being tested.
e.
Click
Apply
.
f.
Click
Yes
in the confirmation dialog box.
Step 4
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.
Step 5
If the test set indicates a faulty circuit, the problem might be a faulty port. Continue with the
“1.2.4 Perform a Hairpin Test on a Destination-Node Port” procedure on page 1-9
.
1.2.4 Perform a Hairpin Test on a Destination-Node Port
The hairpin test is performed on the port in the destination node. To perform this test, you must also
create a bidirectional circuit in the transmit direction from the destination ONS 15310-CL or
ONS 15310-MA to the source node. Creating the bidirectional circuit and completing a successful
hairpin eliminates the possibility that the source port, destination port, or fiber span is responsible for
the faulty circuit.
Create the Hairpin Loopback Circuit on the Destination-Node Port
Step 1
Connect an electrical test set to the electrical port you are testing.
Use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the electrical cabling
panel for the port you are testing.
Step 2
Adjust the test set accordingly.
