debug signalisation process

Unanswered Question
Jul 9th, 2009
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Hello group,

Question: I have an IP network with serveral locations. One location has a special problem. There are 7960 and 7970 IP Phones in use.

When I call to this location, the phone signals but it takes approximately 3 to 5 seconds for a call connect!!!! A call transfer is nearly impossible.

The network access is clean and with 4Mbit high enough. Trace and ping to the CUCM are OK.

No other location has this problem.

My question: How / Which debug can I use to find the problem ?

thx a lot


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Overall Rating: 5 (1 ratings)
Nicholas Matthews Mon, 07/13/2009 - 10:37
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Hi Patricio,

You can do a few things, but so far we have no idea what your call flow is.

Here are debugs for different situations:

FXO/FXS/T1 cas:

debug vpm signal


debug isdn q931


debug h225 asn1

debug h245 asn1


debug ccsip message


debug mgcp packet


debug sccp messages

You'll also want:

debug voip ccapi

Turn on this global command:

service timestamp debug datetime msec local

That will help you find out where the delay is in your network.

On your voice gateway, also use:

show voice dsp detail

Make sure that you don't have a message that says ! Non-default firmware is in use

or make sure your flash does not have: guido.dsp, hdv2.dsp, or dsp_c5510.rbf in your flash.



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