Cisco ONS 15454 - Create the Facility Loopback on the Destination DS-1, DS-3, DS3 N-12, DS3 i-N-12, or EC-1 Port

1-28
Cisco ONS 15454 Troubleshooting Guide, R8.5
November 2009
Chapter 1 General Troubleshooting
1.2.5 Perform a Facility Loopback on a Destination-Node Electrical Port (East to West)
Figure 1-15 Facility Loopback on a Circuit Destination DS-N Port
Caution Performing a loopback on an in-service circuit is service-affecting. To protect traffic, apply a lockout or
Force switch to the target loopback port. For basic instructions, refer to the “2.9.2 Protection Switching,
Lock Initiation, and Clearing” section on page 2-262. For more information about these operations, refer
to the “Maintain the Node” chapter in the Cisco ONS 15454 Procedure Guide.
Note Facility loopbacks require on-site personnel.
Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback.
Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48
card can be provisioned to transmit AIS for a terminal loopback if desired.
Depending on your card type, complete the “Create the Facility Loopback on the Destination DS-1,
DS-3, DS3N-12, DS3i-N-12, or EC-1 Port” procedure on page 1-28 or the “Create the Facility Loopback
on the Source DS3E or DS3XM Port” procedure on page 1-29. Then test and clear the loopback as
instructed.
Create the Facility Loopback on the Destination DS-1, DS-3, DS3N-12, DS3i-N-12, or EC-1 Port
Step 1 Connect an electrical test set to the port you are testing:
a. If you just completed the “1.2.4 Perform a Terminal Loopback on a Destination Electrical Port
(West to East)” procedure on page 1-22, leave the electrical test set hooked up to the
destination-node port.
b. Use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the EIA
connectors or DSx panel for the port you are testing. The Tx and Rx terminals connect to the same
port.
Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)
Step 3 In CTC node view, double-click the card to open the card view.
Step 4 Click the Maintenance > Loopback tabs.
Step 5 Choose OOS,MT from the Admin State column for the port being tested. If this is a multiport card,
select the appropriate row for the port being tested.
Step 6 Choose Facility from the Loopback Type column for the port being tested. If this is a multiport card,
select the appropriate row for the port being tested.
Destination
ONS Node
DS-N OC-NXC
Source
ONS Node
Intermediate
ONS Node
Test Set
DS-N XC OC-N DS-N XC OC-N
115964