topic Re: SIP trunk problem in Spark Firewall (SMB)

SIP trunk problem

RS_Daniel — Mon, 31 Mar 2025 13:54:27 GMT

Hello Community,

I am facing an issue with VoIP and wanted to see if anyone con help us. Some details about our scenario:

2 X 1900 gateways in HA, centrally managed.

Local PBX is behind the gateway.

3 external PBX are connected to the cluster.

The local PBX is NATed with a different IP address for the external PBX's.

This gateway manages 3 SIP trunks, all have the topology Proxy to Proxy, according to ATRG: VoIP, access and NAT rules are configured according the the ATRG. One of them is used only for outgoing calls, this one is working fine. The other 2 SIP trunks are used for incoming calls. These have problems (one way audio only). After we connect the SIP trunks, it works fine for 1-2 days, after that the phone that initiates the call (it is outside the network) does receive audio correctly, however the internal phone has no audio. After some tshooting, we noticed the SIP payload is not NATed correctly so the external PBX does not send the SIP ACK packet and RTP.

Our workaround is to move the SIP trunk connection, to a locally managed 1430 appliance, here it works fine all the time. When we need to replicate the problem, we move the SIP trunk back to 1900 cluster, wait 1-2 days and the issue appears again.

I wanted to ask if someone faced a similar behavior and could provide some guidance. We have a case open for this issue, but did not find a solution yet and customer is getting nervous with this issue.

Any help will be greatly appreciated, thanks in advance.

Regards

Re: SIP trunk problem

PhoneBoy — Wed, 02 Apr 2025 19:15:41 GMT

That sounds like a bug that needs to be addressed.
At least you have some sort of workaround you can employ in the meantime.

Re: SIP trunk problem

info-overload — Mon, 07 Apr 2025 10:06:31 GMT

Just setting up new 1900.

On Prem PBX external SIP Trunk.

SIP 1 way audio. Outbound audio only.

On call with TAC.

R81.10.15 upgraded to R81.10.17

Still working on the problem.

Re: SIP trunk problem

info-overload — Mon, 07 Apr 2025 10:53:12 GMT

Call automatically drops at 1:38

Re: SIP trunk problem

info-overload — Tue, 08 Apr 2025 05:08:33 GMT

TAC discovered it was SmartAccel

Re: SIP trunk problem

RS_Daniel — Tue, 08 Apr 2025 14:05:46 GMT

Hi,

your 1900 gateways are locally managed? i my case they are centrally manged which does not support smart accel.

Re: SIP trunk problem

PhoneBoy — Tue, 08 Apr 2025 16:21:57 GMT

SmartAccel is still SecureXL under the hood.
Which may be where the issue lies in this case, definitely involving TAC

Re: SIP trunk problem

info-overload — Mon, 28 Apr 2025 02:37:39 GMT

Managed by Infinity Portal and Local.

Still having SIP Trunk problem.

4th time contacting TAC about SIP Trunk Audio.

Works for 3 days then 1 way audio.

Different fixes each time.

Re: SIP trunk problem

info-overload — Wed, 14 May 2025 02:29:18 GMT

Update.

Problem still happened with all acceleration disabled.

New firmware version fixed it.

Re: SIP trunk problem

info-overload — Sun, 15 Jun 2025 12:27:47 GMT

New GA firmware available that I think includes a fix for SIP Trunk problems.

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