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Monitoring and Testing
4-20
3166-A2-GB20-10
November 1998
Starting a Line Loopback
The Line Loopback command (LLB) loops the received signal on the network
interface back to the network without change.
98-15946
CSUDSU
NETWORK
INTERFACE
ALL 1s
LLB
PORT 1
" Procedure
To perform a Line loopback:
1. From the top-level menu screen, select Test.
2. From the Test screen, select Lpbk.
F1
Test:
Rlpbk Lpbk Ptrns
F2
F3
3. From the Loopback screen, select LLB.
F1
Loopback:
Abort LLB PLB
F2
F3
Test Started appears on Line 2. If a Line loopback is already in progress, the
Already Active message appears. If an invalid combination of loopbacks is
in progress, the error message Invld Test Combo appears (see Table 4-7 for
valid loopback test combinations).