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ISDN BRI INTERFACE CONFIGURATION
COMMANDS
loopback (ISDN BRI interface view)
Syntax loopback { b1 | b2 | both }
undo loopback
View ISDN BRI interface view
Parameter b1: Places the B1 channel in external loopback.
b2: Places the B2 channel in external loopback.
both: Places both B1 and B2 channels in external loopback.
Description Use the
loopback command to sets the B1, B2, or both channels on the ISDN BRI
interface in external loopback. This can send data from a line back to the line.
Use the
undo loopback command to restore the default.
By default, loopback is disabled on ISDN BRI interfaces.
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CAUTION: The modules with loopback-supported ISDN interfaces include 4BS
(MIM), and 1BS1BU2BS2BU (SIC). In addition, loopback is also supported by the
fixed ISDN interfaces on your router, if there is any.
Example # Place the B1 and B2 channels on interface BRI 1/0 in external loopback.
<Sysname> system-view
[Sysname] interface bri 1/0
[Sysname-Bri1/0] loopback both
