Issue receiving incoming faxes since version 22.1.1

Hello everyone,

since version 22.1.1, I have the issue that I cannot receive incoming faxes. What is the cause of this? Is it related to T38? In the previous version 20.11, I had no issues with the same configuration. Thanks in advance for your help!

-- Accepting AUTHENTICATED call from 127.0.0.1:4570:
    --        > requested auth methods = (MD5),
    --        > actual auth method = MD5,
    --        > encrypted = no,
    --        > requested format = alaw,
    --        > requested prefs = (),
    --        > actual format = alaw,
    --        > host prefs = (alaw|ulaw),
    --        > priority = mine

...
    -- Executing [+123456789@fax-in:12] ReceiveFAX("PJSIP/fax-in-00000036", "/var/spool/hylafax/recvq/20250129-124526-+123456789.tif,df") in new stack
    -- Channel 'PJSIP/fax-in-00000036' receiving FAX '/var/spool/hylafax/recvq/20250129-124526-+123456789.tif'
       > 0x55cc20cfd920 -- Strict RTP learning after remote address set to: 2xx.xx.xx.xx(Provider IP)  
...
       
       > 0x55cc20cfd920 -- Strict RTP switching to RTP target address 2xx.xx.xx.xx(Provider IP):33364 as source
       > 0x55cc20d620a0 -- Strict RTP switching to RTP target address 2xx.xx.xx.xx(Provider IP):33376 as source
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 000.220081 ], stack sent 10 frames (200 ms) of silence.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 000.498915 ], channel sent 25 frames (500 ms) of energy.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 002.820101 ], stack sent 130 frames (2600 ms) of energy.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 002.880090 ], stack sent 3 frames (60 ms) of silence.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 004.240091 ], stack sent 68 frames (1360 ms) of energy.
       > 0x55cc20d620a0 -- Strict RTP learning complete - Locking on source address 2xx.xx.xx.xx(Provider IP):33376
       > 0x55cc20cfd920 -- Strict RTP learning complete - Locking on source address 2xx.xx.xx.xx(Provider IP):33364
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 016.540084 ], stack sent 615 frames (12300 ms) of silence.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 017.920087 ], stack sent 69 frames (1380 ms) of energy.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 018.038932 ], channel sent 377 frames (7540 ms) of silence.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 019.978819 ], channel sent 97 frames (1940 ms) of energy.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 020.020093 ], stack sent 105 frames (2100 ms) of silence.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 020.098844 ], channel sent 6 frames (120 ms) of silence.
Channel 'PJSIP/fax-in-00000036' fax session '52', [ 021.120103 ], stack sent 55 frames (1100 ms) of energy.

There’s not really enough information. Is T.38 in use? What actually happens? (The log doesn’t show anything)

Hi Jacob,

I don’t know if T.38 is in use; I don’t see any frames while sending.

But I found out that adding this before “ReceiveFAX” did solve the problem for incoming facsimiles:

same => n,Dial(IAX2/iaxmodem1) ; I created a secondary iaxmodem for incoming facsimiles...(I forgot to dial iaxmodem1)
same => n,ReceiveFAX(${FAXFILE}) ; <– Is this needed when using Dial for iaxmodem1?

If you’re using iaxmodem, then you Dial it like that. The use of ReceiveFAX receives the fax directly in Asterisk.

1 Like

I never needed the Dial before and used the iaxmodem. Or did I misunderstand something?

I configured the iaxmodem in the iax.conf and never needed the Dial in version 20. However, since version 22, I do. I was trying to set up a second instance with version 20 and Hylafax in a VM earlier, but it’s all becoming too complicated for me with the iaxmodem and Hylafax.

With the last setup from my previous post, the incoming fax works, but now I no longer receive a PDF, instead I get a .tif file. I needed to change now my /var/spool/hylafax/etc/FaxDispatch from “FILETYPE=tif” to “FILETYPE=pdf”.

To use iaxmodem you have to Dial it. That’s the way it works. If nothing dialed it, then it doesn’t sound like you were actually using it.

Ok as I understood that I don’t need ReceiveFAX?

Correct, if using iaxmodem then you don’t need it.

1 Like

Thanks for this information.
And for an outgoing facsimile, am I correct in saying that I dial my SIP provider and not the iaxmodem?