Cisco ASR 1000 Configuration Guide

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Cisco ASR 1000 Series Aggregation Services Routers SIP and SPA Software Configuration Guide
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Chapter 20 Troubleshooting the Serial SPAs
Performing Basic Interface Troubleshooting
Note The output of the show interfaces serial command will vary depending on the type of serial
SPA.
This section describes how to use the show interfaces serial command to diagnose serial line
connectivity problems in a wide-area network (WAN) environment. The following sections describe
some of the important fields of the command output:
• Serial Lines: show interfaces serial Status Line Conditions, page 20-3
• Serial Lines: Increasing Output Drops on Serial Link, page 20-7
• Serial Lines: Increasing Input Drops on Serial Link, page 20-8
• Serial Lines: Increasing Input Errors in Excess of 1 Percent of Total Interface Traffic, page 20-9
• Serial Lines: Troubleshooting Serial Line Input Errors, page 20-10
• Serial Lines: Increasing Interface Resets on Serial Link, page 20-13
• Serial Lines: Increasing Carrier Transitions Count on Serial Link, page 20-14
Serial Lines: show interfaces serial Status Line Conditions
You can identify five possible problem states in the interface status line of the show interfaces serial
display:
• Serial x is down, line protocol is down
• Serial x is up, line protocol is down
• Serial x is up, line protocol is up (looped)
• Serial x is up, line protocol is down (disabled)
• Serial x is administratively down, line protocol is down
The following example shows the interface statistics on the first port of a 4-Port Clear Channel T3/E3
SPA installed in subslot
0 of the SIP located in chassis slot 5:
Router# show interfaces serial
Serial5/0/0 is up, line protocol is up
Hardware is SPA-4T3E3
Internet address is 110.1.1.2/24
MTU 4470 bytes, BW 44210 Kbit, DLY 200 usec,
reliability 255/255, txload 234/255, rxload 234/255
Encapsulation HDLC, crc 16, loopback not set
Keepalive set (10 sec)
Last input 00:00:05, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 40685000 bits/sec, 115624 packets/sec
5 minute output rate 40685000 bits/sec, 115627 packets/sec
4653081241 packets input, 204735493724 bytes, 0 no buffer
Received 4044 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
4652915555 packets output, 204728203520 bytes, 0 underruns
0 output errors, 0 applique, 4 interface resets

Cisco ASR 1000 Specifications

General

Brand	Cisco
Model	ASR 1000
Category	Network Router
Language	English