Cisco ASR 1000 Series Software Configuration Guide

PurposeCommand
Specifies the loopback mode.
• local—Loops back after going through the
framer toward the terminal.
• dte—Loops back after the LIU towards the
terminal.
• network—Loops back towards the network.
• remote—Sends FEAC to set remote in loopback.
• line—Loops back toward network before going
through framer.
• payload—Loops back toward network after
going through framer.
• diag—Loops back after going through the
HDLC controller towards the terminal.
T3/E3
Router(config-if)# loopback {local | dte | network
{line | payload} | remote}
T1/E1
Router(config-controller)# loopback {local [line |
payload] | diag}
Verifying Loopback Mode
The following example shows that local loopback is set:
Router# show interfaces serial 2/0/0
Serial2/0/0 is up, line protocol is up (looped)
Hardware is SPA-4T3E3
MTU 4470 bytes, BW 44210 Kbit, DLY 200 usec,
reliability 255/255, txload 225/255, rxload 221/255
Encapsulation FRAME-RELAY, crc 16, loopback set (local)
Keepalive set (10 sec)
LMI enq sent 13281, LMI stat recvd 13280, LMI upd recvd 0, DTE LMI up
LMI enq recvd 1, LMI stat sent 0, LMI upd sent 0
LMI DLCI 1023 LMI type is CISCO frame relay DTE
FR SVC disabled, LAPF state down
Broadcast queue 0/256, broadcasts sent/dropped 0/0, interface broadcasts 0
Last input 00:00:07, output 00:00:00, output hang never
Last clearing of "show interface" counters 1d12h
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 612756
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 38446000 bits/sec, 109217 packets/sec
5 minute output rate 39023000 bits/sec, 110854 packets/sec
14601577951 packets input, 642478074437 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 parity
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
14545044296 packets output, 639982568049 bytes, 0 underruns
0 output errors, 0 applique, 1 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
rxLOS inactive, rxLOF inactive, rxAIS inactive
txAIS inactive, rxRAI inactive, txRAI inactive
Cisco ASR 1000 Series Aggregation Services Routers SIP and SPA Software Configuration Guide, Cisco IOS
XE Everest 16.5
342 OL-14127-17
Troubleshooting the Serial SPAs
Verifying Loopback Mode

Cisco ASR 1000 Series Specifications

General

Series	ASR 1000
Category	Network Router
Operating System	Cisco IOS XE
Memory	Up to 64 GB
Interfaces	10 Gigabit Ethernet
Power Supply	AC or DC options
Dimensions	Varies by model
Encryption	IPsec, SSL
Storage	Varies by model
Operating Temperature	32°F to 104°F (0°C to 40°C)
Humidity	5% to 95% non-condensing
MTBF	Varies by model