Summary:	ASTERISK-26948: Fax does not work using T.38 passthrough
Reporter:	r (royj)	Labels:
Date Opened:	2017-04-18 02:10:02	Date Closed:	2017-04-28 04:39:00
Priority:	Minor	Regression?
Status:	Closed/Complete	Components:	Channels/chan_sip/T.38 Resources/res_pjsip_t38
Versions:	13.15.0	Frequency of Occurrence	Constant
Related Issues:
Environment:	Debian GNU/Linux 7.8 (wheezy)	Attachments:	( 0) 164409568_164409598.pcap ( 1) 2017-04-20_ASTERISK-JIRA-26948.pcap ( 2) 2017-04-20_debug_log_26948.txt ( 3) fax_13.15.0_pjsip.pcap ( 4) pjsip_faxing_debug.txt ( 5) pjsip_faxing.pcap
Description:	Asterisk 13.15.0 does not  pass through T.38. There is successfull SIP negotiation, but T.38 stucks in Asterisk. There is 't38pt_udptl=yes,redundancy' for peers. IP dump attached.
Comments:	By: Asterisk Team (asteriskteam) 2017-04-18 02:10:02.784-0500 Thanks for creating a report! The issue has entered the triage process. That means the issue will wait in this status until a Bug Marshal has an opportunity to review the issue. Once the issue has been reviewed you will receive comments regarding the next steps towards resolution. A good first step is for you to review the [Asterisk Issue Guidelines|https://wiki.asterisk.org/wiki/display/AST/Asterisk+Issue+Guidelines] if you haven't already. The guidelines detail what is expected from an Asterisk issue report. Then, if you are submitting a patch, please review the [Patch Contribution Process|https://wiki.asterisk.org/wiki/display/AST/Patch+Contribution+Process]. By: r (royj) 2017-04-18 02:11:55.163-0500 fax T.38, IP dump By: r (royj) 2017-04-18 02:18:40.432-0500 Asterisk is 85.114.2.44 By: Rusty Newton (rnewton) 2017-04-19 15:45:41.326-0500 We require additional debug to continue with triage of your issue. Please follow the instructions on the wiki [1] for how to collect debugging information from Asterisk. For expediency, where possible, attach the debug with a '.txt' file extension so that the debug will be usable for further analysis. Thanks! [1] https://wiki.asterisk.org/wiki/display/AST/Collecting+Debug+Information By: Rusty Newton (rnewton) 2017-04-19 15:46:23.679-0500 For the debug log, make sure that you include a new pcap that matches it. By: r (royj) 2017-04-20 03:28:48.827-0500 Files 2017-04-20_debug_log_26948.txt, 2017-04-20_ASTERISK-JIRA-26948.pcap attached By: r (royj) 2017-04-20 03:31:10.678-0500 Asterisk is 172.19.126.106 By: Matthew Fredrickson (mattf) 2017-04-20 09:34:22.193-0500 Is this a new problem in 13.15.0 (i.e. did it work in 13.14.0)? By: r (royj) 2017-04-20 09:54:44.933-0500 Discovered that behaviour in 13.14.0-rc2 and then we updated to 13.15.0. By: Matthew Fredrickson (mattf) 2017-04-21 09:54:00.219-0500 What I'm trying to figure out is if this is a regression.  What was the last known version of Asterisk to work? By: r (royj) 2017-04-21 13:14:10.272-0500 Potentially was Asterisk 11. Give me a time to make sure. By: r (royj) 2017-04-24 01:37:14.973-0500 Same result in 11.4.0. Don't know when it began, we saw it in 13.14.0-rc2 By: r (royj) 2017-04-24 01:39:00.080-0500 What actions should we perform to help to resolve this issue? By: Rusty Newton (rnewton) 2017-04-24 19:06:30.834-0500 Can you do a comparison test with the res_pjsip/chan_pjsip driver? That will help us pinpoint whether the issue is underlying the channel drivers or not. By: r (royj) 2017-04-25 04:19:06.750-0500 Same picture with pjproject-2.6 By: r (royj) 2017-04-25 04:20:55.004-0500 file fax_13.15.0_pjsip.pcap with pjsip attached By: Rusty Newton (rnewton) 2017-04-26 15:46:11.559-0500 Oh! Can you attach your debug log for the PJSIP example? Thanks! By: r (royj) 2017-04-27 02:48:11.525-0500 attached pjsip_faxing.pcap pjsip_faxing_debug.txt By: Joshua C. Colp (jcolp) 2017-04-27 11:38:09.651-0500 Can you also please do a test with "udptl set debug on" done to ensure that Asterisk is seeing and processing the UDPTL traffic? Additionally - do you have iptables on the system that could be blocking the traffic? By: r (royj) 2017-04-28 01:09:31.877-0500 I'm so ashamed of your time spent ( There is actually iptables rules that blocked ports used for udptl. Now faxing works as expected. Thank you for your time!