3Com SuperStack II Reenable the WAN port by entering, Enable V.54 signal detection by entering

142APPENDIX A: TROUBLESHOOTING

5Reenable the WAN port by entering:

SETDefault !3 -PATH CONTrol = Enable

Failure to perform this step causes the port to remain in loopback mode preventing connectivity through the port. Performing diagnostics on the port will reveal only that the port is down.

Performing a Remote To perform a remote loopback test for V.54 on a T1/FT1 port, you must Loopback for V.54 on first connect two SuperStack II NETBuilder SI bridge/routers, or connect

a T1/FT1 Port your bridge/router to a remote device that supports V.54 signal detection.

To perform the remote loopbacktest for V.54, follow these steps:

1Disable the WAN path by entering

SETDefault !3 -PATH CONTrol = Disable

2Enable V.54 signal detection by entering:

LPBCK !3 -PATH V54LpbckYes

3Start the loopback test by entering:

LPBCK !3 -PATH V54LpbckSTART

4Stop the loopback test by entering:

LPBCK !3 -PATH V54LpbckSTOP

Performing a Remote	This section describes how to perform a remote loopback test for ATT on
ATT Loopback Test on	a T1/FT1 port. Connect your bridge/router to a remote device that
the T1/FT1 Port	supports ATT.
	To perform the remote loopback test for ATT, follow these steps:

1Disable the WAN path by entering:

SETDefault !3 -PATH CONTrol = Disable

2Start the loopback test by entering:

LPBCK !3 -PATH RmATTLnLpbckSTART (for a line loopback test)

or

LPBCK !3 -PATH RmATTPyldLpbckSTART (for a payload loopback test)

LPBCK !3 -PATH V54LpbckSTART

3To stop the loopback test, enter:

LPBCK !3 -PATH RmATTLnLpbckSTOP (for a line loopback test)

or

LPBCK !3 -PATH RmATTPyldLpbckSTOP (for a payload loopback test)