- Nortel Network Multiservice Platform User's Guide

Operation, administration, and maintenance (OAM) features 2-57
Planning and Ordering Guide—Part 1 of 2 NTRN10AN Rel 12.1 Standard Iss 1 Apr 2004
— shelf processor restarts
— software upgrades
• Terminal and facility loopbacks are not maintained;
— during network element power cycles
— during brownouts
— when a restart is performed on a circuit pack in a shelf not containing
a shelf processor
• A facility with a loopback cannot be put in-service and it cannot be deleted.
• In-service roll-overs should not be performed on a card with a loopback
operated.
• A facility loopback cannot be operated if;
— the circuit pack is not physically present
— the facility state is in-service
— the facility is provisioned as a TAP
• A data communications channel (DCC) connection to a network element
should not be used to initiate a SONET loopback if the loopback interrupts
communication between the network element and the user. If DCC
communications are interrupted, there will be no way to release the
loopback.
Note 1: If at least one DCC remains active on the network, the user may
still communicate with the network element.
Note 2: GR-253-CORE recommends that facility loopbacks be positioned
at the point immediately following the optical-to-electrical interface. This
is not supported on all circuit packs.
• To operate a loopback, the facility must be OOS-MA.
• Loopbacks are only to be operated for facility testing. Loopbacks are not
to be operated at any other time.
The 2x100BT-P2P and 2XGigE/FC-P2P circuit packs supports both terminal
and facility loopbacks for testing purposes. The loopback can be performed on
a per-channel basis.
Refer to Figure 2-32 on page 2-58 for details on 2x100BT-P2P loopback types.
Note: For descriptive and procedural information about Ethernet
loopbacks, see:
– OPTera Packet Edge System Planning Guide, NTRN10YK
– OPTera Packet Edge System Network Applications and
Management Guide, NTRN11YK