3Com Router 3031, Command Reference Manual

Page: 177 / 838

Fundamental CT1/PRI Interface Configuration Commands 177
Parameter
local: Enables the CT1/PRI interface to perform local loopback.
remote: Enables the interface to perform remote loopback.
Description
Using the loopback command, you can enable a CT1/PRI interface to perform
loopback. Using the undo loopback command, you can disable the CT1/PRI
interface to perform loopback.
By default, the interface is disabled to perform loopback in any form.
Loopback is used to check the condition of interface or cable. This function should
be disabled when they are in normal operation.
If a serial interface formed by bundling timeslots of the CT1/PRI interface is
encapsulated with PPP and is set to perform loopback, it is normal for the state of
the link layer protocol to be reported as DOWN.
Example
Set the interface T1 1/0/0 to perform local loopback.
[3com-T1 1/0/0]loopback remote
pri-set Syntax
pri-set [ timeslot-list range ]
undo pri-set
View
CT1/PRI interface view
Parameter
range: The number of the timeslots that are bundled, which is in the range of 1 to
24. When specifying the timeslots to be bundled, you can specify a single timeslot
by specifying a number, a range of timeslots by specifying a range between
number1-number2, or several discrete timeslots by specifying number1,
number2-number3.
Description
Using the pri-set command, you can bundle the timeslots of a CT1/PRI interface
into a pri-set. Using the undo pri-set command, you can remove the timeslot
bundle.
By default, no timeslots are bundled into pri-set.
When performing pri-set bundling on a CT1/PRI interface, you should note that
you are not allowed to bundle only timeslot 24, because it is the D channel for
transmitting signals. Attempts to bundle only timeslot 24 will fail.