Monitoring and Troubleshooting302768-C Rev 00 6-5• line-loopia sends a CI loopback message, indicating that it originates at theCSU. The signal does not go through the framing device.• line-loopib sends a CI loopback message, indicating that it originates at theDSU. The signal does not go through the framing device.• deactivate-ll disables generation of FDL line loopback codes.• deactivate-all sends a universal loopback deactivate code to stop all loopbackactivity.The following example shows how to start and stop payload loopback over slot 2,connector 1, T1 channel 4:t1-test/t1-2/1/4# send-fdl-loopback-code payload-loopt1-test/t1-2/1/4# send-fdl-loopback-code deactivate-allt1-test/t1-2/1/4#Enabling or Disabling Loop Retention Detection and Interframe FillBy default, the Versalar 15000 neither detects nor transmits loop retention signals.To enable (or again disable) loop retention signals, go to the T1 or FT1 prompt(for example, t1/2/1/4 or ft1/2/1/5) and enter the following command:fdl-loop-interframe-fill {loop-retention | mark}loop-retention enables the use of signals. If the DS1 is in a loopback state, it doesthe following:• Periodically sends loop-retention signals to the remote end• Exits the loopback state if it no longer detects loop-retention signals from theremote endmark (the default setting) disables the use of loop retention signals.In a loopback state, a DS1 does the following:• Does not send loop-retention signals to the remote end• Remains in the loopback state even if it detects remote loop-retention signals.The following example shows how to enable and disable loop retention on slot 2,connector 1, T1 channel 4:t1/2/1/4# fdl-loop-interframe-fill loop-retentiont1/2/1/4# fdl-loop-interframe-fill markt1/2/1/4#
