I have done a few Asterisk builds over the years but never got past installing for one reason or another. Whilst at afreinds hous last week I saw his implementation of FreePBX on Pi.
I happened to have a PI ( with trashed XBMC image ) that I could use , and also found some cheap nortel phones for £8 each.
Installed freepbx and incrediblePBX onto.
Got the phones registered, able to make and recive calls with two way audio.
Only issue is the phones don’t ring!! the handset icon does indicate an incomming call but no ring at all.
So I connected csipsimple on my android tab.
That can recive calls but not make them for some reason ( to be looked into ) . But that does not ring either…
a SIP invite or the unistim equivalent causes the phone to know it is time to ring, if it doesn’t then the problem lies with the phone, check your SIP debug to see if the invite is sent.
Ebay often has very good deals on Polycoms, I like Yealink for “cheap and cheerful”, Aastras for it’s good old Nortel heritage and function. Be careful with older Cisco’s.