U&D works, we’ve played around with it for the same reasons. If you plan to use other modules/features, they may not work as intended, nor is there support for modules when you are in U&D. Even then there are options, such as having a second FreePBX box, to get more features in the extension mode.
Lastly, if it fits your use case, consider using the Sangoma IP phones. They come with a login/logout app that will let you log in and out without having to go into U&D mode.
I don’t know about “no” sense, but there are other devices in the PBX that work better for a bunch of people working in a group, especially if you want people to be “logging in and out”.
It sounds like you operationally want a queue. Shared Line Appearance is intended to one “extension” that happens to live in three places (like you’d have in a house). It sounds like you are actually setting up a calling queue, in which case, every extension should have its own number and the phones get “logged in” to the queue so they’ll ring.
Well as someone who comes from a background where Asterisk has been the only system used that __did not __ support multiple contacts to a single AOR, this is actually more common than you think.
Common scenario: Myself and 3 others must all get calls for a specific reasons. None of these calls,should touch or route to our primary extensions. The calls, if not answered, should end up in a specific voicemail. So with the ability to do Parallel Forking, you create a single extension that can support X contacts and they all get called following that extension’s rules.
Sure you could do a ring group but then you’re just creating three new extensions + a voicemail (possibly) to do the exact same thing. Call X contacts for Y seconds and to go Z mailbox if no answer/busy.
Pure Asterisk solves this problem in a different way. Unfortunately we get into an area of terminology which causes a lot of confusion as extension means something different in Asterisk from its meaning in FreePBX.
In traditional telephony, there is the concept of an equipment number and a directory number. What you want to call to contact these three people is actually a directory number, which Asterisk calls an extension. However FreePBX calls something closer to the equipment number the extension, and then generally confuses the directory and equipment numbers. I think it uses the term virtual extension for the case where a directory number doesn’t correspond to an equipment number.
So, with pure Asterisk, you can have different equipment numbers that are associated into a single directory number by using a special syntax for the Dial application arguments. Also, with pure Asterisk, there is no automatic means of making a call, from outside, to a particular equipment number, there has to be explicit provision, in the dialplan, to map the directory number to one or more equipment numbers. (In fact best security practice is to make directory numbers and equipment numbers different, although that is not commonly followed, and FreePBX is based on not doing that.)
SIP multiple registration further complicates this by doing a similar split with the equipment number, splitting it into an address of record, which is closer to a directory number and a contact address, which is closer to an equipment number.
However, although, with pjsip, this mechanism can also be used parallel call multiple devices, the split into multiple devices is less explicit, with the result that I’m seeing people asking about how to send calls to just one of the devices.
I read through that twice. It is a masterful expression of how this stuff works. It can be confusing, and the nature of what we do here in FreePBX makes the original question a tough one to answer because of the comingling of extension and equipment numbers.
Where I come from, the location number is defined in terms of horizontal and vertical addresses (punch-down blocks in a demark). Thanks for the explanation.