I would like to seek your assistance in on whether you guys have experience in some of our current FAX issues we are experiencing. When we are sending a fax from a traditional fax machine to the Fax Server, it receives it and it works fine. But when we are performing a test fax from the FAX server to the same fax server (loop), we are having isses. below is a simple diagram of the setup we have.
I can see the call being setup between the Adtran and the cisco router and hits the fax server but showing "IP errors received". Not sure where the issue now. It seems the fax negotiation is not establishing. Below is our current trunk configuration on the adtran. According to our client, they do not have this problem when performing the same test to other PSTN services.
voice trunk T02 type isdn
resource-selection circular ascending
connect isdn-group 1
t38 redundancy high-speed 3
t38 redundancy low-speed 2
t38 error-correction fec
t38 ecm disable
rtp delay-mode adaptive
The Configuring and Troubleshooting Fax and Modem Calls in AOS guide goes over tips that may help you. However, this may be an issue that we should work on with a regular Technical Support ticket. ADTRAN Technical Support can be reached by calling 888-423-8726.
We may need debug output to verify that fax tones are recognized and T.38 is negotiated properly. Then a packet capture may be required to verify T.38 packets.
I went ahead and marked this post as assumed answered, but feel free to add any updates or questions you may have.