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Input Error Generated on Serial Interface

We have migrated our voice system from multiplexer to VOIP solution. However, there were a lot of errors generated at one of the router (1721) when we attempted to put off the multiplexer and connecting two sites with routers directly.

I would like to understand if I need any special changes during putting off the MUX. Any comments will be appreciated, thank you.

Below is the information of my network configuration:

Exisitng network: 3745 -- MUX1 ---Wan--- MUX2 -- 1721

Proposed network with error: 3745 ---Wan--- 1721

Existing Serial Interface Setting of 1721:

interface Serial0

description Connecting to MUX

bandwidth 256

no ip address

encapsulation frame-relay

no fair-queue

frame-relay traffic-shaping


interface Serial0.104 point-to-point

Description Connecting to 3745

bandwidth 256

ip address

frame-relay interface-dlci 104

Proposed Serial Interface Setting of 1721:

interface Serial0

Description Connecting to 3745

bandwidth 256

ip address

Error Generated on the Serial Interface after changes:

SH#sh int s0

Serial0 is up, line protocol is up

Hardware is PowerQUICC Serial

Description: 256 Frame-Relay line

Internet address is

MTU 1500 bytes, BW 256 Kbit, DLY 20000 usec,

reliability 181/255, txload 1/255, rxload 1/255

Encapsulation HDLC, loopback not set

Keepalive set (10 sec)

Last input 00:00:00, 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: 234

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 1000 bits/sec, 2 packets/sec

5 minute output rate 1000 bits/sec, 2 packets/sec

109306 packets input, 14420879 bytes, 0 no buffer

Received 5711 broadcasts, 7 runts, 0 giants, 0 throttles

260059 input errors, 6787 CRC, 252924 frame, 0 overrun, 0 ignored, 348 abort

238717 packets output, 26842280 bytes, 0 underruns

0 output errors, 0 collisions, 34 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

DCD=up DSR=up DTR=up RTS=up CTS=up


Re: Input Error Generated on Serial Interface

The 'show interface' output you have given shows the encapsulation as HDLC. Check if it has to be frame-relay or HDLC depending on your requirement.

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