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Un able to send or receive packets

I am un able to send or receive packets across my WAN. Surprisingly the statics of the show interface command of routers on both ends of the WAN shows something like this.

Serial1/3 is up, line protocol is up

Hardware is CD2430 in sync mode

Description: Connecting NTCHEU CCC

Internet address is

MTU 1500 bytes, BW 128 Kbit, DLY 20000 usec, rely 135/255, load 1/255

Encapsulation HDLC, loopback not set, keepalive set (10 sec)

Last input 00:00:00, output 00:00:00, output hang 5d22h

Last clearing of "show interface" counters never

Input queue: 0/75/0 (size/max/drops); Total output drops: 699

Queueing strategy: weighted fair

Output queue: 0/1000/64/679 (size/max total/threshold/drops)

Conversations 0/50/256 (active/max active/max total)

Reserved Conversations 0/0 (allocated/max allocated)

5 minute input rate 0 bits/sec, 0 packets/sec

5 minute output rate 0 bits/sec, 0 packets/sec

255018 packets input, 16955412 bytes, 0 no buffer

Received 106160 broadcasts, 0 runts, 3 giants, 0 throttles

5932220 input errors, 3520772 CRC, 0 frame, 0 overrun, 0 ignored, 2411421 abort

366882 packets output, 112003269 bytes, 0 underruns

0 output errors, 0 collisions, 140948 interface resets

0 output buffer failures, 0 output buffers swapped out

222 carrier transitions

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

On the other end of the WAN the Serial interface of the router has as its ip address and interface statics show that the line protocol is up as well. The line I am using is a 14.4k inetrfaced by codex modems.

Would anyone know what could be causing this surprising scenario?

Is high CRC(3520772 CRC) something to do with the line, router or the modem?


Re: Un able to send or receive packets

IP address on Serial 1/3 is

IP address on the serial interface of the router on the other end is, and I assume the mask is /24 (or also.

The two serial interfaces are not configured to be in the same network/subnet. One is in, the other is in

As long as they are not in the same subnet, they won't pass information back and forth. Once you resolve this by putting both interfaces in the same subnet, the two routers should see each other via ping and telnet.

Once this is done, make sure each router knows how to reach the other router's attached subnets, by using either static routes, or a routing protocol such as RIP, OSPF, IGRP, or EIGRP.

Hope this helps.