[Asterisk-Users] Can someone explain the 's' extension

[Eric "ManxPower" Wieling]

Neil Cherry wrote:
> Eric "ManxPower" Wieling wrote:
>> Neil Cherry wrote:
>>> Does someone explain the 's' extension? In the Wiki it says it's
>>> the catch all extension. In the Asterisk 1.2-rc1 it say it isn't
>>> but doesn't say anything more. Needless to say I'm confused.
>>
>> When a call comes into Asterisk (PSTN, VoIP, etc) and call has NO 
>> information as to what extension to route to then Asterisk will try 
>> sending the call to extension => s
>>
>> In practice this only happens if you have a voice T-1 (Not PRI) with 
>> no DIDs, or if you have an analog FXO port.
> 
> Wow, thanks guys for the quick response. I'm checking out the
> pdf file (previous list message).
> 
> Funny thing is I can get Asterisk to use the 's' extension as a
> catch all (I use the include => xcontext command). But I needed
> to describe it properly for chapter in a book I'm writing. Man
> I hope I get this stuff right!
> 
> BTW, I'm using SIP extensions to do all my testing. Works great
> (when I remember to include the correct contexts ;-)
> 

exten => s is NOT a "catchall" it's more of a "catch nothing" i.e. it 
only catches calls that have no destination info.  A "catchall" would be 
exten => _.  but that would catch extensions that are not numbers (like 
o, i, t, T, h, etc).  A catch all number extensions would be something 
like exten => _X.

--Eric