This test is destructive.
The DS1 BLB (Board Loopback) Test causes a loopback at the DS1 board edge and tests DS1 board internal circuitry.
This test is destructive and can only be initiated by entering the command test ds1-loop location ds1/csu-loopback-test.
All trunks or ports on the DS1 Interface media module must be busied out using busyout board before running the BLB test.
When the BLB test is initiated, maintenance software sends a message to the DS1 Interface media module. The board sets up the BLB loopback, transmits a test pattern, and verifies that the pattern is received unaltered through the loopback. If the transmitted and received patterns are different, the test fails.
When the test is complete, enter release board to restore all trunks or ports on the DS1 Interface media module to the in-service state.
This test is run on the following maintenance object:
