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Cisco ASR 901 Series Aggregation Services Router Software Configuration Guide
OL-23826-09
Chapter 20 Configuring T1/E1 Controllers
Troubleshooting Controllers
Step 3
controller t1
slot/subslot
Example:
Router(config-controller)#
controller t1 0/0
Sets the controller type. The command has the following syntax:
• slot—Slot number of the interface.
• subslot—0.
Step 4
loopback {diagnostic | local {line|
payload}}
Example:
Router(config-controller)# loopback
local line
Sends the packets from a port in local loopback to the remote end.
• diagnostic—Configures the line card to loop data from the transmit
path to the receiver path.
• local line—Configures the T1 line card to loop the received traffic
back to the remote device after passing them through the line
loopback mode of the framer. The framer does not re-clock or reframe
the incoming traffic.
• local payload—Configures the T1 line card to loop the received
traffic back to the remote device after passing them through the
payload loopback mode of the framer. The framer re-clocks and
reframes the incoming traffic before sending it to the network.
Step 5
exit
Example:
Router(config-controller)# exit
Exits controller configuration mode.
Command Purpose
