The
show interface bri
command displays information about the BRI D channel or about one or more B channels, provided that your router is a TE1 (has a native BRI), as shown in the Figure.
Note: Click on the topology to view the command outputs.
If your router acts as a TEI (has a native BRI), use the
show interface bri
command to monitor the interface and the first B channel. If, on the other hand, the router is a TE2 (has an external terminal adapter), use the
show interface serial
command.
Why Is the Router Spoofing?
The word spoofing indicates that the line is not necessarily up, but
the dialer is forcing the line to masquerade as up. Spoofing is a
state to allow DDR to work (other states are up, down, and so on).
The interface dials on demand in response to the packets being
routed to it. But because no packets are routed to down interfaces,
the interface must pretend to be up (spoof), so that packets will be
routed to it when it is not connected. By default, a router removes
any routes pointing to down interfaces from its routing table. DDR
interfaces with BRI remain in spoofing state, even when one or both
B channels are up.
The command to display the B1 information is
show interface bri 0 1 2.
The Figure displays information on both B channels.