Cisco ASR 9000 Series Command Reference Manual page 1046

loopback (T3/E3)
Examples This example shows how to configure the T3 for a local loopback:
RP/0/RSP0/CPU0:router(config)# controller t3 0/3/0/0
RP/0/RSP0/CPU0:router(config-t3)# loopback local
Related Commands
Command
show controllers e3, on page 1038
show controllers t3, on page 1054
Cisco ASR 9000 Series Aggregation Services Router Interface and Hardware Component Command Reference,
Release 5.3.x
1026
T3, E3, T1, E1 Controller Commands on the Cisco ASR 9000 Series Router
Description
Displays information about the E3 links and hardware and software
drivers for the E3 controller.
Displays information about the T3 links and hardware and software
drivers for the T3 controller.