[asterisk-users] iaxmodem / hylafax receive problem

[Kingsley Tart]

On Mon, 2010-01-18 at 07:03 -0500, Doug Lytle wrote:
> Kingsley Tart wrote:
> >
> > Do you know what I should look at next, or how to get more diagnostics
> > somehow?
> >
> >    
> Record the fax using the record option in your iaxmodem config file.  
> The files will be put into the /tmp or /root/tmp folder.  You can play 
> them back with Audacity.
> 
> This way, you'll be able to compare the audio streams from both the 
> machine that fails and the one that doesn't.

Hi,

I might be making a small bit of progress with this.

On the one that fails, the incoming audio stream gets cut off very early
- a short whistle then a beep, that's it. The audio from the DSP seems
(to my ears) to start the same way for both the successful and
unsuccessful fax call.

I've also noticed that whenever the fax fails, I get "Detected digit
'f'" in the asterisk log (below). It's as if this is received and then
the calling fax machine gives up.

I googled for this message but I couldn't find anything useful. Any idea
what it means? I've turned off faxdetect in chan_dahdi.conf (but it
didn't work with it on either, though the symptoms were different, and
we don't have it on our other Asterisk servers that are working fine).

Cheers,
Kingsley.

PS. in case it helps, here are the sounds (one for a successful fax, one
for a failed one) and below that is a log extract with the "Detected
digit 'f'" entry):


http://212.84.161.26/failed-iaxmodem0-dsp.wav
http://212.84.161.26/failed-iaxmodem0-iax.wav

http://212.84.161.26/success-iaxmodem0-dsp.wav
http://212.84.161.26/success-iaxmodem0-iax.wav

[Jan 18 15:53:31] VERBOSE[3704] logger.c:     -- Called iaxmodem0/08123456789
[Jan 18 15:53:31] VERBOSE[3479] logger.c:     -- Call accepted by 127.0.0.1 (format alaw)
[Jan 18 15:53:31] VERBOSE[3479] logger.c:     -- Format for call is alaw
[Jan 18 15:53:31] VERBOSE[3704] logger.c:     -- IAX2/iaxmodem0-8855 is ringing
[Jan 18 15:53:31] VERBOSE[3704] logger.c: q931.c:2844 q931_alerting: call 19968 on channel 20 enters state 7 (Call Received)
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Protocol Discriminator: Q.931 (8)  len=9
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Call Ref: len= 2 (reference 19968/0x4E00) (Terminator)
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Message type: ALERTING (1)
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > [1e 02 81 88]
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Progress Indicator (len= 4) [ Ext: 1  Coding: CCITT (ITU) standard (0)  0: 0  Location: Private network serving the local user (1)
[Jan 18 15:53:31] VERBOSE[3704] logger.c: >                               Ext: 1  Progress Description: Inband information or appropriate pattern now available. (8) ]
[Jan 18 15:53:31] VERBOSE[3704] logger.c:     -- IAX2/iaxmodem0-8855 answered DAHDI/51-1
[Jan 18 15:53:31] VERBOSE[3704] logger.c: q931.c:2951 q931_connect: call 19968 on channel 20 enters state 8 (Connect Request)
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Protocol Discriminator: Q.931 (8)  len=14
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Call Ref: len= 2 (reference 19968/0x4E00) (Terminator)
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Message type: CONNECT (7)
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > [18 03 a9 83 94]
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Channel ID (len= 5) [ Ext: 1  IntID: Implicit  PRI  Spare: 0  Exclusive  Dchan: 0
[Jan 18 15:53:31] VERBOSE[3704] logger.c: >                        ChanSel: As indicated in following octets
[Jan 18 15:53:31] VERBOSE[3704] logger.c: >                       Ext: 1  Coding: 0  Number Specified  Channel Type: 3
[Jan 18 15:53:31] VERBOSE[3704] logger.c: >                       Ext: 1  Channel: 20 ]
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > [1e 02 81 82]
[Jan 18 15:53:31] VERBOSE[3704] logger.c: > Progress Indicator (len= 4) [ Ext: 1  Coding: CCITT (ITU) standard (0)  0: 0  Location: Private network serving the local user (1)
[Jan 18 15:53:31] VERBOSE[3704] logger.c: >                               Ext: 1  Progress Description: Called equipment is non-ISDN. (2) ]
[Jan 18 15:53:31] VERBOSE[3498] logger.c: < Protocol Discriminator: Q.931 (8)  len=5
[Jan 18 15:53:31] VERBOSE[3498] logger.c: < Call Ref: len= 2 (reference 19968/0x4E00) (Originator)
[Jan 18 15:53:31] VERBOSE[3498] logger.c: < Message type: CONNECT ACKNOWLEDGE (15)
[Jan 18 15:53:31] VERBOSE[3498] logger.c: q931.c:3711 q931_receive: call 19968 on channel 20 enters state 10 (Active)
[Jan 18 15:53:32] DEBUG[3704] chan_dahdi.c: Detected digit 'f'
[Jan 18 15:53:35] DEBUG[3704] chan_dahdi.c: Detected digit 'f'
[Jan 18 15:53:39] DEBUG[3704] chan_dahdi.c: Detected digit 'f'





-- 
Cheers,
Kingsley.