TA908 sending SIP 400 Bad request from 2nd call into a number. I see ERROR! deliverResponse ignored on PRI, but I'm not sure if that's what's causing the SIP 400. Ideas on what's causing the error? The 2nd call is from 4355129105 to 6167727067 and first call is from 4353102745 to 6167727067 that worked properly. I cut out most of the logs from the first call so you can see what's going on with the 2nd call. See attached.
What's the actual setup there? SIP trunk out to the PSTN and PRI to the PBX?
It would be useful to get a debug from the ISDN side. It sounds like the PRI may be sending a cause code back to the TA900 that isn't being mapped properly to SIP. Try the same scenario with "debug isdn l2f" enabled.
What is the PBX supposed to do when a second call comes in to a number that is in use? Usually they either go to local voicemail or accept the call and signal call-waiting to the user. Or it will send ISDN cause 17 user busy, which the TA900 should translate to SIP 486 and play a busy signal to the caller. It sounds like the PBX is returning a cause code that the TA900 can't handle, but the mapping can be changed once we determine what is happening.
What is the PBX supposed to do when a second call comes in to a number that is in use?
It's supposed to go to a different channel or send a cause code 17. We're not seeing that in this case. See Rob's attachment and let us know if you have any ideas. Thanks.
The attachment didn't seem to show a second call to the same number. It did show a cause 100 invalid_elem_contents which could be an ISDN switch type mismatch. It also showed the ISDN number plan as being unknown. You should probably configure an ISDN number template of type "national" on the TA900 for ten-digit calls.
isdn-number-template 1 prefix “ ” national NXXNXXXXXX