SIP CUBE Faxing to CUCM - RightFax not working

[corneliss]

Hi All,

I need some help, we have recently started moving from MGCP Gateways to SIP CUBE on our Routers as the PRI quality was not good.

I have Ported my Fax Range to the new ISP and currently having trouble receiving Faxes when it hits my CUBE.

Please we have a SIP Trunk between CUCM and our RightFax Server and I can confirm is working for all MGCP Gateways.

When doing a call to my FAX number using the CUBE I do hear the Fax tones but the call is dropped after 3 seconds.

This means all routing is correct but it seems like connection is dropping.

I have read online it might be because I'm sending g729 and g711ulaw to my Fax but can confirm when changing the Codec the call fails instantly.

I have not worked with Faxing before and it's extremely hard to troubleshoot.

any suggestions or ways to use RTMT to see what the issue is. 

Or has someone else using RightFax used their CUBE Gateway for Faxing and got it working.

Thanks in advance.

[corneliss · Accepted solution]

Hi Kevin, sorry for not responding.

I can confirm the issue has been resolved after forcing G.711a on my incoming dial-peer for my Fax Range to CUCM.

We also recreated a Device Pool just for Fax and Region and confirmed G.711 is used between the Fax Sip Trunk and the CUBE.

This has resolved the issue, thanks again for the help from your side.