[Asterisk-Users] Virtual PBX setup.

[Michael Welter]

zimdog wrote:
> I am wondering what has been done as far as running multiple instances 
> of *. Like if you were providing a virtual PBX for small companies. I 
> imagine it can be done in one of the following ways  and am looking to 
> see how other users are doing it. I have searched the wiki and have not 
> found any info related to this. Maybe I am using the wrong word to 
> describe what I want.
> 
> 
> 1) Segment the companies up in the extensions.conf file - This could 
> handle the incoming outgoing calls but would have to share other 
> configuration options in the other config files like moh etc.

I'm looking at this as well.  I think Asterisk's "context" feature can 
be used to partition the PBX for multiple clients.  When a call arrives 
on a T-1, the DID number will cause the call to be routed to that 
client's [incoming-call-x] context.  The client's extensions would be 
defined in the [default-x] context, and each client would have a 
[local-x] context for outbound calling rules.  I haven't tried this yet, 
but I don't see why it wouldn't work.

> 
> 2) Install multiple instances of * on the same machine - Seems like a 
> good choice any problems with this and documentation on what needs to be 
> done?

Red flags here.  I'm not sure if multiple instances of Asterisk would be 
able to share the Zap channels known to the zaptel module--could 
channels 1-12 belong to Asterisk instance #1 and channels 13-24 to 
instance #2?  Probably not.  You also have the problem with 
/var/run/asterisk.pid.

> 
> 3) Run inside of a virtual server environment like vmware or virtual 
> linux server. - Seems like a good choice also. Anyone have any 
> experience using * in this situation?

Wouldn't you still have physical circuits attached to physical boxes, 
each box running an instance of Asterisk?

I'm exploring a file server based system, with diskless "call servers" 
mounting their file systems from the file server.  All configuration and 
voicemail files will reside on the file server.  The file server will be 
server-grade hardware with RAID, while the call servers will be 
relatively cheap desktop quality hardware.  All boxes will have two NIC 
interfaces on the MB, one a public interface and the other a private 
interface for inter-system IAX traffic.  Each call server will have just 
a two- or four-port T-1 card in a 1U rack-mount chassis.

Each "extension" on the Cisco 79xx can be configured to register to a 
particular IP address, so each phone can be registered across two or 
more call servers.  I'm thinking that the failure of a call server won't 
necessarily bring the system down, just degrade the service.  Plugging 
the T-1 circuit(s) into a spare call server and powering-up the box 
would restore the system.

Comments anyone?