1-7
Cisco ONS 15310-CL and Cisco ONS 15310-MA Troubleshooting Guide, R7.0
78-17235-01
Chapter 1 General Troubleshooting
1.2.3 Perform a Terminal Loopback on a Destination-Node Port
c.
Set the circuit Type and Size to the normal preferences, such as STS and STS1.
d.
Uncheck the Bidirectional check box and click
Next
.
e.
In the Circuit Source dialog box, select the same Node, Slot, Port, and Type where the test set is
connected and click
Next
.
f.
In the Circuit Destination dialog box, use the same Node, Slot, Port, and Type used for the Circuit
Source dialog box and click
Finish
.
Step 4
Confirm that the newly created circuit appears on the Circuits tab list as a one-way circuit.
Step 5
Continue with the
“Test the Hairpin Circuit” procedure on page 1-7
.
Test the Hairpin Circuit
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 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 with the hairpin loopback circuit.
Clear the hairpin circuit:
a.
Click the
Circuits
tab.
b.
Choose the hairpin circuit being tested.
c.
Click
Delete
.
d.
Click
Yes
in the Delete Circuits dialog box.
e.
Confirm that the hairpin circuit is deleted from the Circuits tab list.
Step 4
If the test set indicates a faulty circuit, there might be a problem with the port. Continue with the
“1.2.3 Perform a Terminal Loopback on a Destination-Node Port” procedure on page 1-7
.
1.2.3 Perform a Terminal Loopback on a Destination-Node Port
The terminal loopback test is performed on the node destination port in the circuit. First, create a
bidirectional circuit that originates on the source node electrical port (such as DS-1, DS-3, or EC-1) and
terminates on the destination-node electrical port. Then continue with the terminal loopback test.
Completing a successful terminal loopback to a destination-node port verifies that the circuit is good up
to the destination port.
Caution
Performing a loopback on an in-service circuit is service-affecting.
Create the Terminal Loopback on a Destination-Node Port
Step 1
Connect an electrical test set to the port you are testing:
a.
If you just completed the
“1.2.2 Perform a Hairpin on a Source-Node Port” procedure on page 1-6
,
leave the electrical test set connected to the electrical port in the source node.
