I configured Asterisk 10 for inbound fax, for couple of weeks I didn’t see any issues until today. The setup I configured for inbound fax is quite simple i.e. Cisco Voice GW sends the fax calls to Asterisk using T.38 protocol and later Asterisk stores/forwards the fax to specific end user.
The configuration I made in sip.conf for enabling T38 is listed below;
t38pt_udptl = yes,fec,maxdatagram=400
faxdetect = t38
And in udptl.conf, I just uncommented ‘use_even_ports = yes
;’ and rest of it set as default.
Here is the error I’m usually seeing in Asterisk side;
[Jan 15 14:13:28] NOTICE udptl.c: UDPTL (SIP/10.3.22.6-00000ad6): Transmission error to 10.3.22.6:18428: Resource temporarily unavailable
If this notice comes, it occurs repeatedly unless I need to restart the asterisk service. For some reason it also effecingt the V-GW. There is no issue found in the V-GW side.
Please advise what is the reason that I’m getting this message and how can I avoid it?