I have clients with 4 voip phones that have the same extension assigned to them.
lets say the extension is 500
They want to be able to intercom by dialing *80500 from one of the four phones and have the other 3 phones auto answer the intercom call.
The issue that I am having with the setup is if i try this from one of the 4 phones with the same extension I get a message “intercom for extension 500 is disables” even though it is enabled.
If I try the same thing from a phone on a different extension it works just like it should (all 4 phones auto answer the intercom call)
So why does it not work from one of the four phones with same extension?
Because when you answer a call, the extension 500 is ‘bound’ to the ip address of that phone, SIP would only send that new call back to you with negative effect,
I think this is happening because of FreePBX logic, not because of binding of an IP address. Even if this done using chan_pjsip multiple contacts, addresses are only bound to the contact, and that is at registration time, not call set up time. If it just done with & in the dial string, the Asterisk core has no idea that multiple endpoints correspond to the same Asterisk extension
but perhaps someone figured out that that;s not a good idea.