We are getting a heap of faxes failing for one of our tenants. The SIP trace is showing the BYE record coming from the Vital PBX. The numbers are correct, and they do connect successfully, but then the BYE record is coming early and coming from the PBX disconnecting the fax.
I (master tenant) have logged in to the tenancy and sent the same fax to the same number and it was successful. I havent tested this at scale, just one.
What would be causing this? I am new to Vital and am at a loss. Many faxes are successful, but a great many also fail. Customer is not happy.
Hi @miguel our provider does support t38 however, interestingly, that particular fax record that we are chasing, was sent as a normal G711A audio call, not a t38.
Why would a fax from the system not be sent correctly as a t38? Is there some settings I should check?
Does using a Trunk work for eFax? I cant see how to make the two work together? Is there documentation on this?
I will also upgrade the PBX, but did see a user in the forum say his upgrade caused big issues on this system. No one replied to him but I am a bit nervous to do that, can you confirm that there is no issue?
Hi @miguel are you able to confirm upgrade the PBX will not cause issues? And are you able to provide some instructions for the Trunk for fax in the individual tenant, I cannot find anything in the wiki.
@miguel I have created that trunk and it looks all good, but faxes are still failing? I am not sure if I am missing a step. I am not able to see anywhere where I can link that trunk to the fax specifically.
@miguel thanks for these instructions, they were great and I was able to set it up on the two tenants who fax, but unfortunately, it crashed the whole PBX for inbound calls for all tenants. It began to just “read digits” and stopped routing correctly.
I deleted the fax trunks and all returned to normal.
So hundreds of angry customers and still no resolution to the fax issue.
It seems there’s been a misunderstanding. Please note that you don’t need to create new trunks. Instead, you can share your existing trunks with your tenants and use them directly with the fax devices.
This approach ensures that your current setup is used efficiently without requiring additional configuration.
If I understand correctly, I think the key information here is: you need to select Class of Service = All Permissions (not default trunk) for this trunk (fax trunk) if it is used for a sub-tenant. That way, the trunk connected to the customer’s fax can use your main tenant trunk, based on the outbound profile you have set for that tenant. The alternative is setting up a separate class of service for this tenant only and assigning this to the trunk.