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not 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?


Re: not able to send or receive packets

One could be the high number of input errors, CRC, and interface resets from the show interface command output. Another is that the two serial interface IP addresses do not belong to same network and I assume you cannot even ping the serial interface, both sides, even if it shows "UP", "UP".

Here's the link for troubleshooting serial line problems:



Re: not able to send or receive packets