Outbound FXS Fax Issue

[j-macdonald]

It's been years since I've done faxing over FXS and am in a situation now where I have to get it running. I have configured the port,  dial-peer, and a route pattern of 303272 to point to the proper route list on CUCM 7.1.5. Inbound faxing works, but, outbound however just gives a fast busy. They're using a fractional E1 as PSTN and outbound voice calls to the PSTN work fine.

voice-port 0/1/0
cptone NL
description Fax-Operations
station-id name 3170301XXXX
station-id number 70301XXXX

!

dial-peer voice 3273 pots
description Ops Fax
destination-pattern 303273
port 0/1/0
!

dial-peer voice 1 pots
destination-pattern 00T
progress_ind setup enable 3
incoming called-number .
direct-inward-dial
port 0/0/0:15
forward-digits all
!
dial-peer voice 2 pots
destination-pattern 0T
progress_ind setup enable 3
progress_ind progress enable 8
progress_ind connect enable 8
incoming called-number .
direct-inward-dial

port 0/0/0:15
prefix 0
!

I'm know I'm close but this is driving me crazy. I can't remember for the life of me if I'm missing something....

Thanks for any replies in advance

John

[Michael Hanes]

Hi John,

Fast busy signals almost always point to a call routing issue. Does this fax machine have an analog handset attached to it or can you plug in an analog handset into the FXS port? You say outbound voice works but I want to confirm that if you use an analog handset on this same port, voice calls work. If you dial the same number that you are dialing for faxing, your calls should have the same result as the fax calls. Can you confirm/clarify outbound voice calls dialing the same number you dial for fax calls?

I am also a little confused about the topology. Are you wanting the FXS fax calls that are headed outbound to just go out the E1 port on this same local router? If so, I do not se a VoIP dial peer to get this to CUCM for routing. I just see POTS dial peers and 303272 does not appear to match any of them. Can you confirm the number that you are dialing on the FXS fax machine when you hear the fast busy?

Basically, you should approach this problem as a voice call routing problem. All fax calls set up as voice calls first. It is not a fax problem at this point as the fax devices are not even connecting and setting up the initial voice connection. I hope this helps.

Regards,

David

[j-macdonald]

Hi David,

Thanks for the reply. Sorry, I forgot to include my catch all voip dial-peer

dial-peer voice 10 voip
preference 1
destination-pattern .T
progress_ind setup enable 3
no modem passthrough
session target ipv4:172.xx.x.x
incoming called-number .
voice-class codec 1 
voice-class h323 1
dtmf-relay h245-alphanumeric
ip qos dscp cs5 media
ip qos dscp cs3 signaling
no vad

Yes, I'm trying to get the local support guy to plug an analog phone into the fax and test dial. More to follow.

John

[Michael Hanes]

Hi John,

If my hunch is correct, when the local handset is connected and the same number is dialed, the same fast busy should be heard. The voice gateway does not know the difference between a fax machine and a handset so the call will route the same if the same digits are sent. If this occurs then you have a VoIP call routing problem.

By the way, your question motivated me to post a document here on CSC involving the FoIP troubleshooting.  Here it is if you are interested -

https://supportforums.cisco.com/docs/DOC-14150

Regards,

David