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New Member

Fax PRI to BRI

Hello All,

I'm currently trying to install a fax solution. An incoming call on E1 PRI should be forwarded to an ISDN BRI(Fax server).

My PRI and BRI's are H.323 configured. Using ISDN debugging, I can see an incoming FAX being forwarded towards the BRI, I can also see they are connected! Great! However, my faxes fail!

This is my setup:

If I test it locally, Fax server sends fax to BRI, BRI Dial peer back to fax server, it works! If I send the fax out over PSTN, it fails! So Server sends fax to BRI, out on PRI, back in on PRI and then again back out on Bri to server, ISDN is connected however, fax fails!!!

Any ideas???

Thanks in advance!

  • Unified Communications Applications

Re: Fax PRI to BRI


Can you post your config?

Is there a specific error on your fax? Does it train up at all?

Can you post a debug ISDN Q931?

How have you set up your clocking?



New Member

Re: Fax PRI to BRI

Hello there Tim,

Are there any errors: Not during ISDN setup. Everything appears to be working fine. :-(

There appears to be some problem during the training phase because that's wher it goes wrong. I can post you a debug but nothing can be seen in it. It's perfect...

In attachement a debug for a call from fax server going out over BRI, then out to PSTN over PRI, coming back in from PSTN over PRI and back BRI to the fax server. You can see that the sending fax disconnects... normally!!

thanks for the help!