calls dropped after session-expires is reach

[Luis C]

Hello,

conference phones (grandstream GAC 2500) calls are been dropped with 488 Not Acceptable Here.
The scenario is:
phone-----------------------------------------------------------3CX----------------------------------------SIPTruk
INVITE (no sesión-expires) -> INVITE (no sesión-expires)
? <- 200 OK (Session-Expires: 1800;refresher=uas)
...
? <- re-INVITE (Session-Expires: 1800;refresher=uac)
-> 488 Not Acceptable Here

The 488 is just generated after 15 minutes of ACK message, that is, when re-INVITE is received by 3CX following the sesión-expires header.

This is the re-INVITE:
INVITE sip:[email protected]:5060 SIP/2.0
Via: SIP/2.0/UDP 10.1.6.201:5060;branch=z9hG4bK796n5e20cg3lh77cjql0.1
Max-Forwards: 69
From: <sip:[email protected]:5060>;tag=as75b0010d
To: "G-04 Sala de Consolas"<sip:[email protected]:5060>;tag=2369252d
Contact: <sip:g0*[email protected]:5060;transport=udp>
Call-ID: _LZlkXDWp-JuAKfFzqRZ6g..
CSeq: 102 INVITE
Session-Expires: 1800;refresher=uac
Min-SE: 90
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH, MESSAGE
Supported: replaces, timer
Content-Type: application/sdp
Content-Length: 273
v=0
o=cooper 1438790713 1438790713 IN IP4 10.1.6.201
s=-
c=IN IP4 10.1.6.201
t=0 0
m=audio 8034 RTP/AVP 0 8 101
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-16
a=silenceSuppff - - - -
a=maxptime:150
a=sendrecv

I would like to know how 3CX manage sesión-expires.
Note I can check this scenario working properly, that is, we have calls with more 15 minutes duration but in these cases calls are dropped.

Regards,
Luis Carlos

 

[craigreilly]

Are you programming manually?
I have a Template I use for the 2500, and have no complaints of them ever dropping a call.
I can share if you like.