Cisco ASR 1000 Series Software Configuration Guide

SolutionPossible ProblemStatus Line Condition
1
Put the line in local loopback
mode and use the show
interfaces serial command to
determine whether the line
protocol comes up.
If the line protocol
comes up, a failed
Note
remote device is the
likely problem.This
solution will only work
with High-Level Data
Link Control (HDLC)
encapsulation. For
Frame Relay (FR) and
Point-to-Point Protocol
(PPP) encapsulation, a
looped interface will
always have the line
protocol down. In
addition, you may need
to change the
encapsulation to
HDLC to debug this
issue.
2
If the problem appears to be on
the remote end, repeat Step 1
on the remote interface.
3
Verify all cabling. Make certain
that the cable is attached to the
correct interface, the correct
CSU/DSU, and the correct
remote termination point.
4
Enable the debug serial
interface EXEC command.
5
If the line protocol does not
come up in local loopback
mode, and if the output of the
debug serial interface EXEC
command shows that the
keepalive counter is not
incrementing, a router hardware
problem is likely. Swap router
interface hardware.
6
If the line protocol comes up
and the keepalive counter
increments, the problem is not
Cisco ASR 1000 Series Aggregation Services Routers SIP and SPA Software Configuration Guide, Cisco IOS
XE Everest 16.5
328 OL-14127-17
Troubleshooting the Serial SPAs
Serial Lines: show interfaces serial Status Line Conditions

Cisco ASR 1000 Series Specifications

General

Brand	Cisco
Model	ASR 1000 Series
Category	Network Router
Language	English