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hdlc ping problem

hi guys

i have configure my router to hdlc

to cinnect to a remote router

bith side are hdlc

one side can ping its own serial address but i can not ping my own ip address or the remote ip address.

line protocol is also up on bith side

any idea please?


Re: hdlc ping problem

Hi ,

R u pining from PC which is connected in LAN are u doing the test....

Can you explain it clearly...

If you are trying from pc which is connected in LAN make sure that


2.ip assigned to PC are correct...

Can you paste the config of both the routers.



Community Member

Re: hdlc ping problem


thank you for your reply

i am ping from the router inside

here is the sho interface:

Serial2/0:23 is up, line protocol is up

Hardware is DSX1

Internet address is

MTU 1500 bytes, BW 128 Kbit, DLY 20000 usec,

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

Encapsulation HDLC, loopback not set

Keepalive not set

Last input never, output 00:00:20, output hang never

Last clearing of "show interface" counters never

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 14

Queueing strategy: weighted fair

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

Conversations 0/1/256 (active/max active/max total)

Reserved Conversations 0/0 (allocated/max allocated)

Available Bandwidth 96 kilobits/sec

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

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

0 packets input, 0 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort

286 packets output, 18370 bytes, 0 underruns

0 output errors, 0 collisions, 4 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

Timeslot(s) Used:24-25, Transmitter delay is 0 flags

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Re: hdlc ping problem


I am guessing that there is a mismatch between the routers in their addressing - perhaps a mismatch of subnet mask. I see that this router uses a /30 mask. Is it possible that the router on the other end of the connection is using a different mask (or perhaps a different address)?



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