Issue Dialing 911 Across SCN Out PRI

[RocketJTech]

Greetings Friends,

I am having difficulty pinpointing the cause of a 911 issue on an inherited system. The System is a 2-location SCN, with the only trunk being a PRI connected to System A. The issue is that whenever 911 (or 9,911) is dialed from System B, the caller only hears continuous ringing on the line, while the 911 dispatcher receives and answers the call, hearing only dead air. This has been tested from several phones. 911 calls originating from System B are all as described, but any other calls behave as they should. All calls from System A behave as they should. I am attaching Monitor traces from both systems. The calls in question occur at 14:43:17 - 14:43:51 (dialing 911), and 14:44:14 - 14:44:45 (dialing 9911). Both calls originated from x207, on System B.

Additional Information:
Both Locations are R11.0, Preferred Edition with Voicemail Pro (upgraded about 1.5 years ago)
Phones are 9620L and 9608G models.
Systems are networked over dedicated fiber
System A IP Address: 10.114.4.3 / VLAN 55
System B IP Address: 10.114.8.3 / VLAN 8

System A SCN Line Short Code - 9N/N/Dial/58

System A - ARS (58) Short Codes (Line Group 9 = PRI):
11/Dial Emergency/911Ns5636590750/9
911/Dial Emergency/911Ns5636590750/9
0N;/Dial 3K1/0Ns5636590750/9
1N;/Dial 3K1/1Ns5636590750/9
XN;/Dial 3K1/Ns5636590750/9
XXXXXXXXXXN/Dial 3K1/Ns5636590750/9

System B - ARS Short Codes (Line Group 17 = SCN Line):
11/Dial Emergency/9911/17
911/Dial Emergency/9911/17
0N;/Dial 3K1/90N/17
1N;/Dial 3K1/91N/17
XN;/Dial 3K1/9N/17
XXXXXXXXXXN/Dial 3K1/9N/17


Any advice in troubleshooting is appreciated. Thank you.

Sometimes, I feel like a kindergartner missing out on recess, because certain kids won't shut up and get in line.

 

[NYSTECH]

Turn off Direct media path on the SCN trunk if it isn't.

 

[RocketJTech]

Thank you for the suggestion, but the "Allow Direct Media Path" options are ALL unchecked throughout both systems.

Sometimes, I feel like a kindergartner missing out on recess, because certain kids won't shut up and get in line.

 

[TouchToneTommy]

Try

System B - ARS Short Codes (Line Group 17 = SCN Line):
11/Dial 3K1/9911/17
911/Dial 3K1/9911/17

Maybe turn off SIP tracing in your Monitor for more readable output.
Actually, maybe just Call/Call Delta/Targeting/ARS on the Call tab, everything on the ISDN tab, Error and Print on the System tab, on System A when System B places a test 911 call

 

[RocketJTech]

Thank you, Tommy. I tried, as you suggested, Changing the "Dial Emergency" actions to "Dial 3K1" with the same result. Dispatcher receives call and answers to only dead air, while the caller's end just continues to ring, as if there is no signal received that the call has been answered. I am attaching the Monitor Trace for the call, using the settings that you requested.

Sometimes, I feel like a kindergartner missing out on recess, because certain kids won't shut up and get in line.

 

[RocketJTech]

I have created and attached another document. This is a comparison of 2 Monitor traces. The first is the same one from my last post. Immediately following it is a trace of a call from the same phone to my cell phone (a successful call). Both traces start out to be very similar, but at a certain point, they begin to differ quite a bit. It is at this point where I believe the problem may be found. I highlighted that point in both traces, so you can find it easily. On the successful call, there is a "connected" message, where there is no such message on the 911 call. I hope somebody can make sense of this information. Thank you for trying.

Sometimes, I feel like a kindergartner missing out on recess, because certain kids won't shut up and get in line.