HDLC not working

Unanswered Question

Hi Experts,

We have 2 sites interconnected with WAN links. The WAN connectivity is based on Serial P2P links. However the problem that we are facing is that when we configure the HDLC protocol at both ends, the line protocol remains down even though both side routers are Cisco(Cisco 2600 series). We are able to bring the Line Protocol up with the PPP.

Please can someone advise as to what could be the possible reason for the same and suggest some points that we can check.

Many thanks in advance.

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Overall Rating: 3 (1 ratings)
Paolo Bevilacqua Sat, 08/04/2007 - 06:24
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that is really strange. You would need to send "show interface" for both routers when either HDLC or PPP is configured, doing "clear counters" in between.

Richard Burts Sat, 08/04/2007 - 13:13
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I agree with Paolo that this is really strange. Is it possible that one router was configured with no keepalive when it was configured for HDLC? In addition to the request for posting the output of show interface I believe that it would be very helpful if you would post the interface configuration, both when configured as HDLC (and not working) and when configurd as PPP and working.



Paolo Bevilacqua Sun, 08/05/2007 - 00:34
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Correct, default keepalive 10 seconds.

Please do not change this default and leave keepalive active unless there is a proved reason to change that.

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