Avaya 03-300430 User Manual

This test is destructive.
The CSU Equipment Loopback (ELB) test causes a loopback at the near-edge of the local 
120A1 CSU module or the 401A T1 sync splitter and tests the connection from the DS1 board to 
the CSU module/T1 sync splitter (DS1 board edge interconnecting cable, and CSU module/T1 
sync splitter edge). This test is only performed if the 120A1 CSU module or the 401A T1 sync 
splitter is present, administered, and connected to a 1.544-Mbps DS1 circuit pack on the back 
of the port carrier.
The test is destructive and can only be initiated by a system technician demanded test 
ds1-loop location ds1/csu-loopback-tests command.
Each trunk or port on the UDS1 Interface circuit pack must be busied out using the busyout 
board location command before running the ELB test.
When the ELB test is initiated, maintenance software sends an appropriate message to the 
UDS1 Interface circuit pack to start the test. The board sets up the ELB loopback, transmits a 
test pattern, and verifies that the pattern is received unaltered through the loopback. If the 
transmitted and received pattern is different, the test fails.

0

NO

BOARD

The test could not relate the internal ID to the port (no board). This could 
be due to incorrect translations, no board is inserted, an incorrect board is 
inserted, or an insane board is inserted.

1. Verify that the board’s translations are correct. Execute add ds1 

location to administer the UDS1 interface if it is not already 

administered.

2. If the board was already administered correctly, check the error log to 

determine whether the board is hyperactive. If so, the board was shut 
down. Reseating the board will re-initialize it.

3. If the board was found to be correctly inserted in step 1, enter 

busyout board location.

4. Enter reset board location.
5. Enter release board location.
6. Enter test board long location.

This should re-establish the linkage between the internal ID and the port.

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