[asterisk-users] low success rate for ReceiveFax

[Steve Underwood]

On 06/26/2012 11:47 AM, Roi Stork wrote:
> In what way was my question not meaningful? Not enough details?
Enoughj? You didn't give any.
> Here's our current receive fax route:
> sender fax machine -> telco -> E1 line -> sangoma card -> asterisk
>
> We're currently using free fax for asterisk.
This constitutes a meaningful question.
>
> I have read that fax over voip is not reliable, but is it the same
> case for faxes going through dahdi channels?
> It's strange because I previously tested using another asterisk server
> to send fax using SIP to the receiving server above, and the
> completion rate is better than using an actual fax machine.
With a direct PSTN connection like that a success rate of 99% should be 
considered very bad. The log below suggests you have hiccups on the 
audio, and the single commonest reason for that in a setup like yours is 
you are not sourcing the clock for your Sangoma card's E1 interface from 
the PSTN.

Steve
>
> >From the asterisk console I can see the receiving fax session running,
> but halfway it stops due to timeout or hangup.
> Below is a fax session output which was marked as failed:
>
>
> -- Channel 'DAHDI/i1/-4' receiving FAX
> '/var/spool/asterisk/fax/fax-65126150-1340338724-rx.tif'
>
> -- Channel 'DAHDI/i1/-4' FAX session '0' started
>
> -- FAX handle 0: [ 000.000051 ], STAT_EVT_STRT_RX st: IDLE rt: IDLENSRX
>
> -- FAX handle 0: [ 000.000098 ], STAT_EVT_RX_HW_RDY st: WT_RX_HW_RDY
> rt: RRDYNHRY
>
> -- FAX handle 0: [ 000.000129 ], P30EVN_RECEIVE_STARTED
>
> -- FAX handle 0: [ 000.000148 ], STAT_INFO_CSI
>
> -- FAX handle 0: [ 000.000174 ], STAT_INFO_DIS
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 000.079050 ], channel sent 3 frames (60 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 000.093757 ], stack sent 4 frames (80 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 000.153752 ], stack sent 3 frames (60 ms) of silence.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 000.459077 ], channel sent 19 frames (380 ms) of silence.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 003.154772 ], stack sent 150 frames (3000 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 003.199289 ], channel sent 137 frames (2740 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 003.211770 ], stack sent 3 frames (60 ms) of silence.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 003.259286 ], channel sent 3 frames (60 ms) of silence.
> -- FAX handle 0: [ 005.250881 ], STAT_EVT_TX_V21_DONE st: WT_DIS_RSP
> rt: WDSRNT21
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 005.571646 ], stack sent 118 frames (2360 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 005.599474 ], channel sent 117 frames (2340 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 005.799493 ], channel sent 10 frames (200 ms) of silence.
> -- FAX handle 0: [ 007.213920 ], STAT_INFO_DCS
>
> -- FAX handle 0: [ 007.213946 ], STAT_EVT_DCS st: WT_DIS_RSP rt: WDSRNDCS
>
> -- FAX handle 0: [ 007.213969 ], STAT_NEG_V29_9600
>
> -- FAX handle 0: [ 007.213983 ], STAT_NEG_MMR
>
> -- FAX handle 0: [ 007.213995 ], STAT_NEG_A4
>
> -- FAX handle 0: [ 007.214007 ], STAT_NEG_RES_204x98
>
> -- FAX handle 0: [ 007.214019 ], STAT_NEG_ECM
>
> -- FAX handle 0: [ 007.214031 ], STAT_EVT_SW_ECM st: WT_DIS_RSP rt: WDSRNSWE
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 007.279603 ], channel sent 74 frames (1480 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 007.439604 ], channel sent 8 frames (160 ms) of silence.
> -- FAX handle 0: [ 007.553962 ], STAT_EVT_RX_IMG_STRT st: RCV_ECM_TRN
> rt: UNEXPECT
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 009.219725 ], channel sent 89 frames (1780 ms) of energy.
> -- FAX handle 0: [ 009.253979 ], STAT_EVT_RX_TRN_END st: RCV_ECM_TRN
> rt: RTCFNERT
>
> -- FAX handle 0: [ 009.254005 ], STAT_FRM_CFR
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 009.414674 ], stack sent 192 frames (3840 ms) of silence.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 009.459747 ], channel sent 12 frames (240 ms) of silence.
> -- FAX handle 0: [ 010.439088 ], STAT_EVT_TX_V21_DONE st: RCV_ECM_STRT
> rt: RECMNT21
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 010.772670 ], stack sent 68 frames (1360 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 010.799850 ], channel sent 67 frames (1340 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 011.019872 ], channel sent 11 frames (220 ms) of silence.
> -- FAX handle 0: [ 011.132976 ], STAT_EVT_RX_IMG_STRT st: RCV_ECM_STRT
> rt: RECMNSRI
>
> -- FAX handle 0: [ 011.133002 ], P30EVN_PHASE_C
>
> -- FAX handle 0: [ 011.133018 ], P30EVN_DOC_START
>
> -- FAX handle 0: [ 011.133049 ], P30EVN_PAGE_START
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 014.740131 ], channel sent 186 frames (3720 ms) of energy.
> -- FAX handle 0: [ 014.812946 ], STAT_EVT_RX_IMG_END st: RCV_ECM rt: RECMNERI
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 014.860152 ], channel sent 6 frames (120 ms) of silence.
> -- FAX handle 0: [ 016.273967 ], STAT_INFO_PPS_EOP
>
> -- FAX handle 0: [ 016.273993 ], STAT_EVT_PPS_EOP st: F_END_ECM rt: FEEMNP_P
>
> -- FAX handle 0: [ 016.274055 ], P30EVN_PAGE_END
>
> -- FAX handle 0: [ 016.274071 ], P30EVN_DOC_END
>
> -- FAX handle 0: [ 016.274086 ], STAT_FRM_MCF
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 016.340258 ], channel sent 74 frames (1480 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 016.434711 ], stack sent 283 frames (5660 ms) of silence.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 016.480280 ], channel sent 7 frames (140 ms) of silence.
> -- FAX handle 0: [ 017.459594 ], STAT_EVT_TX_V21_DONE st: F_END_ECM rt: FECMNFCS
>
>> Channel 'DAHDI/i1/-4' fax session '0', [ 017.793706 ], stack sent 68 frames (1360 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 017.820355 ], channel sent 67 frames (1340 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 018.020382 ], channel sent 10 frames (200 ms) of silence.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 019.400471 ], channel sent 69 frames (1380 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 019.420496 ], channel sent 1 frames (20 ms) of silence.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 019.460489 ], channel sent 2 frames (40 ms) of energy.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 019.780498 ], channel sent 16 frames (320 ms) of silence.
>> Channel 'DAHDI/i1/-4' fax session '0', [ 019.820519 ], channel sent 2 frames (40 ms) of energy.
> -- Span 1: Channel 0/7 got hangup request, cause 16
>
> -- FAX handle 0: [ 019.879779 ], STAT_EVT_TMR_INT_EXP st: F_END_ECM rt: XXXXNTIX
>
> -- FAX handle 0: [ 022.382966 ], STAT_EVT_HW_CLOSE st: WT_HW_CLS rt: WCLSNCLS
>
> -- FAX handle 0: [ 022.383063 ], STAT_SES_COMPLETE
>
> -- FAX handle 0: [ 022.383083 ], P30EVN_COMPLETE
>
> == Spawn extension (fax-rx, receive, 19) exited non-zero on 'DAHDI/i1/-4'
>
>
>
> On Fri, Jun 22, 2012 at 12:25 PM, Steve Underwood <steveu at coppice.org> wrote:
>> On 06/22/2012 11:58 AM, Roi Stork wrote:
>>> Hi,
>>>
>>> Im able to send faxes with no errors, but the success rate for the
>>> receiving side is less than 50%.
>>>
>>> Asterisk usually returns records these errors as partial fax and fax
>>> protocol error.
>>>
>>> A lot of the error values returned by FAXOPT are 3RD_T2_TIMEOUT and
>>> T2_TIMEOUT.
>>>
>>> Any suggestions on how to improve the fax receiving rate?
>>>
>> "I have a problem. Can you fix it?" is not really a meaningful question.
>>
>> Steve
>>