Rogue calls

[Brian Birmingham]

I am mid deployment on my first 3CX install and I have ran into an issue that I could use some help on. The system is hosted in the Google cloud and is on version 16.0.611. The phones all started getting calls from 11111, 88888, 8000 and other numbers. The calls are all fake/dead air when answered. We are using Grandstream 2615's. I found some threads discussing this and they indicated that I need to change "Accept Incoming SIP from Proxy Only" to Yes in the phones GUI under: Accounts > Account # > SIP Settings > Security Settings. I have done this and it does work. If the phone is reset the setting reverts back to the initial setting and the calls start ringing in again. Is there something in 3CX that needs to be changed or maybe a global setting that will fix all of the phones? Any help would be greatly appretiated.

 

[leejor]

You would have to modify the template used by the set.
https://www.3cx.com/community/threads/grandstream-template.58593/

 

[cobaltit]

I'm assuming you are using STUN. Using a SBC instead would fix the issue.

 

[Saqqara]

How are the phones provisioned - stun or sbc

Can you see the calls hitting the 3cx server , check activity log ? If not I would say the calls are coming thru your router.

If stun configure, restrict the source as the 3cx fqdn for the incoming ports on the firewall

 

[Brian Birmingham]

How are the phones provisioned - stun or sbc

Can you see the calls hitting the 3cx server , check activity log ? If not I would say the calls are coming thru your router.

If stun configure, restrict the source as the 3cx fqdn for the incoming ports on the firewall

All phones stun. I eneded up blocking from the router. Thanks for the reply.