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New Member

Sending FAX issue

Dear All,

I have a fax machine model ( Muratec F 68P) which is terminated on Cisco VG224 , the VG224 is using SCCP  with CUCM 7.1.3 ,the problem is when I need to send a fax from the fax machine I can't send and when I used the fax for a voice call it was successed .

also when using the fax to send a fax I get a strange behaviar , that I get a busy tone for about 5 seconds , then I get normal tone to dial and after I enter the destenation number it makes disconnect after about 10 seconed .

for the call setup ,it is as the following :

Fax ---> VG224 -----> CUCM ------> Voice gateway (MGCP fxo port ) -----> PSTN ------> Fax .

So can any one help me for this issue ?Is there any advice for any item on the call path to be added or checked?


Ahmed Ellboudy 

Cisco Employee

Re: Sending FAX issue

SCCP only supports NSE based switchovers.  You need to configure the MGCP gateway for an NSE based switchover.  Since it is Cisco and POTS on both sides, I'd recommend modempassthrough here.

Do you have this configured?


voice service voip

fax protocol none

modem passthrough nse codec g711u

On PSTN gateway:

mgcp modem passthrough voip codec g711ulaw

mgcp fax t38 inhibit

If you still have issues, collect:

sh run

sh ver

sh call history voice br

And the following from each side during a failure:

debug voip rtp sess name

debug isdn q931

debug mgcp pack

debug voip ccapi inout

EDIT: Had a command wrong.

New Member

Re: Sending FAX issue

Dear Steven,

Thank you for your support ,it is working today by your recommendation.

Best Regards,

Ahmed Ellboudy

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