Shared Extensions yet?

I am trying to share one extension between an office phone and her secretary. so either could pick up a call to that extension or check voicemail or see the mwi. seems like something many people would want to do.

reading the forum, i see several posts from 2007-2009 saying asterisk 1.4 can’t do that and that it’s not being worked on (and work-arounds offered).

is this still the case in 1.6 and 1.8? (ie not supported). still not being worked on?


Either pick up is certainly possible in 1.4 (use & in the Dial application). I am pretty certain that it is possible for voicemail, as that is a device property and only needs to work in the device to extension direction. I don’t know enough about the implementation of MWI, but I wouldn’t be surprised if that also worked in 1.4.

If upgrading, ignore 1.6. Neither it nor 1.4 or supported any longer, except for security issues.

allow me to clarify. i would like to have two separate ip phones registered to the the SAME single extension (x100 for example). then if someone dials x100, BOTH phones ring (first to pick up gets it) and if a voicemail comes in the MWI comes on on BOTH phones.

It’s not hard:

exten => 100,n,Dial(SIP/firstphones&SIP/second)

and in sip.conf for both peers,


skyrun: What may be the cause of the confusion is that phones don’t register to extensions, they register as SIP devices.

Whilst making the device address and the extension number that calls it the same simplifies simple dial plans, it is denying the full flexibility and also makes a hackers job much easier - if you have long, apparently random, device addresses, a hacker can’t try things like 4000 with any luck, and when they have found one, can’t find the rest by just adding 1 repeatedly.

It is possible that some GUIs don’t expose the distinction.

The big elephant in the room is the fact the most popular GUI manager for Asterisk does not allow non-numerical characters in user names. This is true even in the non-standard “devices and users” mode: … k-security