Prevent calling to an extension

[Ronin]

Hello,

We don't want our users to be able to call the number "123" by mistake so we want to hide it with a dial code or something similar.
Hiding the extension 123 from the company's phonebook is not a solution because they can still accidentally call it.
Can this be done?

 

[JohnS_3CX]

Hi,

Try to edit the forwarding rules of the the extension, and add exceptions for extension ranges of persons you don't want calling it.

For example, this extension cannot be called from anyone inside the range starting from 000 to 200

201 and upwards will be able to call it normally.

 

[Ronin]

Hi John,

This configuration will not be optimal because we want the people to be able to call the extension but just not by dialing "123".
For example, we want to create an alarm ring group.
Everyone will know that 123 is for the alarm but they will only be able to call it by pressing for example: *3123.
This is to ensure that no one will be able to ring the alarm by mistake.
Is there a way to do this?

 

[JohnS_3CX]

Ah this is something entirely different then. I'm not aware of a direct way to do this

 

[leejor]

Have you tried using a (dialable) SIP ID, in the extension settings? You could make that a 6 or 7 digit number. I have not checked, to see if a caller, blocked by the above method, can still reach the extension, using that, but worth a try.

 

[Ronin]

Hi Leejor,

I have checked SIP ID, this is a good feature but how can I disable the internal incoming calls to that extension?
For example: Extension 123 has a SIP ID: 0#
Can we disable the incoming calls to 123 but enable them under 0# ?

 

[leejor]

Re-reading this again suggests that the call forward method, given above, is probably going to block (divert) all calls to that extension, from certain numbers.
Unfortunately (for your requirement), 3CX is not really designed to block internal calling as the assumption is, that all extensions are used by employees of the same company, and why would you need to block anyone internally.

As soon as you assign an extension, it becomes dial-able, and it's caller ID would be known if it were to call anyone without blocking caller ID. You can't stop someone from dialling a valid extension number, unless it's done, in the internal dialplan, of the device itself.

Making use of the octothorp (#), in a dialplan may present other issues, as many SIP devices see that character as end of dialling and not an actual digit