[asterisk-users] Multi-homed Asterisk

[Gordon Henderson]

On Thu, 14 Aug 2008, Jon Weisman wrote:

> Hey guys its me again! So I need to setup our Asterisk server with multiple
> IP providers. The server has two NICs, we have two providers, now we want
> redundancy! Any guides on how to set this up? We're running Fedora Core 5 w/
> Asterisk 1.4.
>
> What I would like is that incase one link goes down, or even if the link is
> showing up, but for some reason its not routing traffic the other link
> should take over. This is for both inbound and outbound SIP. Now the hard
> part... I need this to be reliable.
>
> Your help is greatly appreciated,

While this can be done in Linux using iptables, etc. you might find it 
easier to do it outside the box - get a router with 2 WAN ports and a 
single LAN port and use that to connect to the 2 ISPs.

That way you get your whole LAN protected.

This won't give you instant fall-over and certainly won't preserve a call 
in-progress, but if you can weather a 30-second outage while the router 
decides one ISP is dead and switches to the other, it might be good 
enough.

However, all I'll say is what do you think will go wrong, and if both 
wires to the 2 different ISPs go out the same point from the building, 
down the same road/duct/overhead, what happens when a muppet driving a JCB 
comes along and cuts all of them at the same time...

If you still want to do it yourself, inside the box, start here:

   http://lartc.org/howto/

(chapter 4)

That won't give you fall-over, but it's a start...

Gordon