PDU or routing issues

Unanswered Question
Aug 16th, 2010
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When i try to ping my router i get the U caracter :


Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to, timeout is 2 seconds:
Success rate is 0 percent (0/5)


but i can access via telnet to this device.

Does someone know or explain this issue ? is this will cause problems to incoming /out trafic of this remote router ?

Thanks for your reply.


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Overall Rating: 3.5 (2 ratings)
Giuseppe Larosa Mon, 08/16/2010 - 14:34
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Hello Abzaz,

with telnet you try to open  a TCP (protocol 6) session to port 23 (telnet)

with ICMP you send out packet with protocol 1 code echo request

I would say there is an extended ACL allowing telnet and denying ICMP packets

Hope to help



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