Identify Points Of Failure On An Oc-N Circuit Path; Perform A Facility Loopback On A Source-Node Oc-N Port - Cisco ONS 15310-CL Troubleshooting Manual

Chapter 1 General Troubleshooting
b.
c.
d.
e.
The entire DS-N circuit path has now passed its comprehensive series of loopback tests. This circuit
qualifies to carry live traffic.

1.3 Identify Points of Failure on an OC-N Circuit Path

Using facility loopbacks, terminal loopbacks, and cross-connect loopback circuits, you can test OC-N
facilities or STSs on the ONS 15310-CL or ONS 15310-MA to logically isolate faults. For this purpose,
you perform a loopback test at each point along the circuit path to systematically isolate a point of
failure.
The example in this section tests an OC-N circuit on a three-node path protection. Using a series of
facility loopbacks and terminal loopbacks, the path of the circuit is traced and the possible points of
failure are tested and eliminated. A logical progression of seven network test procedures applies to this
sample scenario:
1.
2.
3.
4.
5.
6.
7.
The test sequence for your circuits differs according to the type of circuit and network topology.
Note
Note Facility and terminal loopback tests require on-site personnel.

1.3.1 Perform a Facility Loopback on a Source-Node OC-N Port

The facility loopback test is performed on the node source port in the network circuit, in this example,
the source 15310-CL-CTX or CTX2500 OC-N port in the source node. Completing a successful facility
loopback on this port isolates the OC-N port as a possible failure point. Performing a loopback on an
in-service circuit is service-affecting.
78-17235-01
Choose None from the Loopback Type column for the port being tested.
Choose the appropriate state (IS,AINS; OOS,DSBLD; or OOS,MT) from the Admin State column
for the port being tested.
Click Apply.
Click Yes in the confirmation dialog box.
Facility loopback on the source-node OC-N port
Cross-connect loopback on the source-node OC-N port
Terminal loopback on the source-node OC-N port
Facility loopback on the intermediate-node OC-N port
Terminal loopback on the intermediate-node OC-N port
Facility loopback on the destination-node OC-N port
Terminal loopback on the destination-node OC-N port
1.3 Identify Points of Failure on an OC-N Circuit Path
Cisco ONS 15310-CL and Cisco ONS 15310-MA Troubleshooting Guide, R7.0
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