Which extensions should not be used (already used by system)

Which extensions are set aside for use by the system and should not be used?

It looks like the following as far as I can see:

7777 is used to simulate incoming calls.
888 is used to barge.
666 is to simulate incoming fax.
555 is used for channel spy.

Is that it, or are there others?



there are some asterisk standard extensions fyi.
voip-info.org/wiki/view/Aste … extensions

Your four extensions are not, I beieve, even in the standard Asterisk configuration. They have either been defined locally or are associated with some Asterisk GUI add on.

I’m fairly sure that there are no reserved numeric extension numbers in the Asterisk core, although some are defined in the sample configuration, particularly those in features.conf.

I am using freepbx with asterisk, so they must be freepbx related then.

Thanks though for letting me know… I now know where to look for further information!


they are set up by freepbx and if you use freePBX GUI, simply navigate to the feature codes link, you can see all the extensions used there. as i recall, freePBX has a failsafe mechanism built in so you cannot create an extension that is already used, including already used by features.

ok, thank you