The basics

Can someone explain the basics of setting up multiple trunks with phones that support multiple lines.
At home I have PBX in a Flash with two SIP trunks (Google) and seven 2 line phones. To get this to work, which is has been doing for 3 years, I created 2 extensions per phone on my PBX and registered each phone with each extension - worked great. Extension 101 actually has an account 101 and 201, Extension 102 has an account 102 and 202, etc

I’m now installing a Grandstream ucm6102 at work with eight grandstream GXP 2160 phones and 6 SIP trunks.
I could create 6 extensions per phone, and register each phone to the PBX 6 times. Kinda time consuming.
Am I approaching this the wrong way?

Our needs are very basic. One number, 6 trunks. All phones ring. No DIDs needed. Every phone should be able to pickup and make a call.

Sounds like you need to use ring groups and allow or deny “call waiting” on extensions as appropriate. It’s all in the wiki

Do the phones facilitate to enter 6 separate SIP account settings?
@dicko I think, I would use a queue in this situation (ring group only allows one call at a time, when ringing concurrently - especially with this many trunks)