Specifying The Loopback Mode - Nortel Versalar 15000 Troubleshooting Manual

Monitoring and Troubleshooting
Example - FT1
To prevent slot 2, connector 1, FT1 channel 5 from accepting remote loop-up and
loop-down requests, enter:
accept-loopback-request disabled
ft1/2/1/5#
ft1/2/1/5#

Specifying the Loopback Mode

When the loopback-mode is set, an MCT3 port or a T1 or FT1 interface is
automatically placed in loopback mode, without any request from the remote test
equipment.
Note: The loopback mode setting for each MCT3 port and T1 and FT1
channel is independent. The loopback mode setting for a T1 or FT1 channel
overrides that of its parent MCT3 port. For example, if you set the
loopback-mode parameter for a T1 channel to payload, its value is payload
even if the loopback-mode parameter setting of the MCT3 port is line.
To change the loopback mode, go to the MCT3, T1, or FT1 prompt (for example,
, , or ), and enter the following command:
mct3/2/1 t1/2/1/4 ft1/2/1/5
| |
loopback-mode {payload line disabled}
passes received signals through the T1 framer and through the loop for
payload
retransmission. This mode maintains bit-sequence integrity for information bits,
but it does not maintain frame or superframe integrity.
line bypasses the framing device and passes directly through the loop. This
method ensures minimum penetration.
disabled (the default setting) deactivates any current loopback.
The following example shows how to change the loopback mode to payload on
slot 2, connector 1:
loopback-mode payload
mct3/2/1#
mct3/2/1#
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302768-C Rev 00