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I'm setting up a new Asterisk PBX, and I'm on the process of buying IP phones. I plan to add phones as needed, as we can't afford to buy them all at once. However, I do want to create a single extension for each person in the company, so we can start distributing them to clients.

My plan is to create multiple extensions, one for each person in the company, but have about half the phones. The phones support a single line. On Asterisk (using FreePBX), I would configure something like this:

  2001 -> Phone connected
  2002 -> Phone connected

  2001 -> Rings extension 2001
  2002 -> Rings extension 2002
  2003 -> Rings extension 2001
  2004 -> Rings extension 2002

After we buy more phones, I will unfold the routes, so each number goes to its actual extension.

Will this work in practice? Does anyone have experiences doing something similar to this?

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up vote 1 down vote accepted

Yep that will work just fine. Your dial statement would look like (assuming your peer is named the same as your extensions):

exten => 2001,1,Dial(SIP/2001)

then for 2003:

exten => 2003,1,Dial(SIP/2001)

When you get the new phones in you will just have to change the Dial statement on the extension and you'll be good.

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The only thing you'll have to keep in mind is that ext. 2003 will likely not go to voicemail, but get picked up by the person who thinks the're extension 2001, bleh! – StrangeWill Sep 15 '11 at 20:55
Yep the only way to fix that is with multi-line phones. – Zypher Sep 15 '11 at 20:57
Or dynamically generate your asterisk configs based on who is in the office. – StrangeWill Sep 15 '11 at 21:02
Ah so they arn't in the office at the same time? Are their schedules predictable? – Zypher Sep 15 '11 at 21:04
Assumption on my part, I couldn't imagine two people actively sharing a phone! Hah. – StrangeWill Sep 15 '11 at 21:13

Another thing you can do is change the caller ID information depending on which extension is being called. You can do something like this:

exten => 2001,n,Set(CALLERID(name)=Call for Ext. 2001)
exten => 2003,n,Set(CALLERID(name)=Call for Ext. 2003)

and the incoming number will still show-up, but the name field will show which extension is being dialed...

Another option is to prepend "2001: " or "2003: " to the Caller ID name field if you want to get fancier.

Another way to do it if your phones are multi-line capable, you can assign a different extension to each line, and then line 1 rings ext. 2001 and line 2 rings ext. 2003

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Nice. I'm using FreePBX for the setup, I'll check if it can be done through its interface. – pgb Oct 13 '11 at 19:14

You can create dynamic agents.

So agent= extensions, and person must register fro for that agent/extension.

i.e on working day start enter some number, enter password, after that asterisk "remmember" that agent XXXX on phone YYY. this way you can move users without moving phones.

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