Cisco ONS 15454 Troubleshooting Manual page 5

Chapter 1 General Troubleshooting
3.
4. A facility loopback when the card is in transparent mode on the client or trunk squelches the far end.
The loopback itself is listed in the Alarms window. For example, the window would list the
LPBKTERMINAL condition or LPBKFACILITY condition for a tested port.
In addition to the Alarms window listing, the following behaviors occur:
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•
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Bridged DS-N and OC-N terminal loopback examples are shown in
Figure 1-5 Terminal Loopback on a DS-N Card with Bridged Signal
Test Set
Figure 1-6 Terminal Loopback on an OC-N Card with Bridged Signal
Test Set
November 2004
A facility loopback on the client or trunk squelches the far end.
If a DS-N, OC-N, or EC-1 port is placed in out of service (OOS) state, it injects an AIS signal
upstream and downstream.
If a DS-N, OC-N, or EC-1 port is placed in out of service auto in-service (OOS_AINS) state or in
the out of service maintenance (OOS_MT) state before loopback testing, the port clears the AIS
signal upstream and downstream unless there is a service-affecting defect that would also cause an
AIS signal to be injected. For more information about placing ports into alternate states for testing,
refer to the Cisco ONS 15454 Procedure Guide.
If a TXP_MR_2.5G port is placed in the out of service maintenance (OOS_MT) state before
loopback testing, the port raises an Alarms Suppressed for Maintenance (AS-MT) condition during
the loopback on the client side port.
If a TXP_MR_10G port is placed in the out of service maintenance (OOS_MT) state before
loopback testing, the port raises a Loss of Signal (LOS) alarm on the DWDM-side port during the
loopback.
If an MXP_2.5_10G port is placed in the out of service maintenance (OOS_MT) state before
loopback testing, the port raises a Loss of Signal (LOS) alarm on the DWDM-side port during the
loopback.
Source
ONS Node
DS-N XC OC-N
Source
ONS Node
OC-N XC OC-N
Destination
ONS Node
OC-N XC DS-N
Destination
ONS Node
OC-N XC OC-N
Cisco ONS 15454 Troubleshooting Guide, R4.6
1.1 Network Troubleshooting Tests
Figure 1-5 and Figure 1-6.
Test Set
Test Set
1-5