[Serusers] Unexpected disconnect - lost SIP packets?

[Jeremy A]

Hello,

I'm need some help with SIP protocol / SER configuration to resolve a
problem.

I have a system with a SER instance and a SIP client application running
on the same box.

SER is 10.50.32.10:5060
APP is 10.50.32.10:5070
Remote SIP server 10.1.39.10
Remote phone is 10.1.39.202

The user agent is registered with the SER instance as extension 1009. It
has aliases 1001-1008 and is actually called as 231x which maps onto
100x which then connects to extension 1009.

The remote phone makes a call to the user agent application via the
remote SIP server and the SER instance. It dials 2311 which gets
automagically converted to extension 1009

The call is established but the user application times out and detects a
disconnect despite the calling phone not hanging up. In my wireshark
trace it seems that SER is ignoring some form of keep-alive from the
remote SIP server and this is causing the timeout. The lines of interest
include 39, 42, 45, 50, 53, 56, 59

Lines 28 and others similar are on the loopback interface and are
packets between port 5060 and 5070

Can someone please advise if the SIP protocol has problems and/or if SER
configuration has problems?


 22   0.218826  10.50.32.10 -> 127.0.0.1    SIP Request: REGISTER
sip:localhost.localdomain
 23   0.219570    127.0.0.1 -> 10.50.32.10  SIP Status: 200 OK    (1
bindings)
 24  19.472555   10.1.39.10 -> 10.50.32.10  SIP/SDP Request: INVITE
sip:1001 at butler.fesa.sto;transport=udp, with session description
 25  19.473394  10.50.32.10 -> 10.1.39.10   SIP Status: 100 trying --
your call is important to us
 26  19.473596  10.50.32.10 -> 10.50.32.10  SIP/SDP Request: INVITE
sip:1009 at 10.50.32.10:5070;LINEID=1d5a67e38809, with session description
 27  19.484244  10.50.32.10 -> 10.50.32.10  SIP Status: 100 Trying
 28  19.725476  10.50.32.10 -> 10.50.32.10  SIP Status: 180 Ringing
 29  19.725828  10.50.32.10 -> 10.1.39.10   SIP Status: 180 Ringing
 32  21.770798  10.50.32.10 -> 10.50.32.10  SIP/SDP Status: 200 OK, with
session description
 33  21.782437  10.50.32.10 -> 10.1.39.10   SIP/SDP Status: 200 OK, with
session description
 38  21.789396  10.50.32.10 -> 10.1.39.202  RTCP Source port: 8001 
Destination port: 16391
 39  21.800069   10.1.39.10 -> 10.50.32.10  SIP Request: ACK
sip:2311 at 10.50.32.10:5070;LINEID=1d5a67e38809
 40  22.278096  10.50.32.10 -> 10.50.32.10  SIP/SDP Status: 200 OK, with
session description
 41  22.278713  10.50.32.10 -> 10.1.39.10   SIP/SDP Status: 200 OK, with
session description
 42  22.298101   10.1.39.10 -> 10.50.32.10  SIP Request: ACK
sip:2311 at 10.50.32.10:5070;LINEID=1d5a67e38809
 43  23.285536  10.50.32.10 -> 10.50.32.10  SIP/SDP Status: 200 OK, with
session description
 44  23.288988  10.50.32.10 -> 10.1.39.10   SIP/SDP Status: 200 OK, with
session description
 45  23.307839   10.1.39.10 -> 10.50.32.10  SIP Request: ACK
sip:2311 at 10.50.32.10:5070;LINEID=1d5a67e38809
 48  25.298214  10.50.32.10 -> 10.50.32.10  SIP/SDP Status: 200 OK, with
session description
 49  25.299105  10.50.32.10 -> 10.1.39.10   SIP/SDP Status: 200 OK, with
session description
 50  25.317892   10.1.39.10 -> 10.50.32.10  SIP Request: ACK
sip:2311 at 10.50.32.10:5070;LINEID=1d5a67e38809
 51  29.306496  10.50.32.10 -> 10.50.32.10  SIP/SDP Status: 200 OK, with
session description
 52  29.306758  10.50.32.10 -> 10.1.39.10   SIP/SDP Status: 200 OK, with
session description
 53  29.328420   10.1.39.10 -> 10.50.32.10  SIP Request: ACK
sip:2311 at 10.50.32.10:5070;LINEID=1d5a67e38809
 54  33.314736  10.50.32.10 -> 10.50.32.10  SIP/SDP Status: 200 OK, with
session description
 55  33.318736  10.50.32.10 -> 10.1.39.10   SIP/SDP Status: 200 OK, with
session description
 56  33.338302   10.1.39.10 -> 10.50.32.10  SIP Request: ACK
sip:2311 at 10.50.32.10:5070;LINEID=1d5a67e38809
 57  37.323175  10.50.32.10 -> 10.50.32.10  SIP/SDP Status: 200 OK, with
session description
 58  37.324791  10.50.32.10 -> 10.1.39.10   SIP/SDP Status: 200 OK, with
session description
 59  37.347936   10.1.39.10 -> 10.50.32.10  SIP Request: ACK
sip:2311 at 10.50.32.10:5070;LINEID=1d5a67e38809

--> client detects disconnect here

Thanks

jeremy