[Asterisk-Users] How to use multiple VOIP provider trunks

[Joseph Gutowski]

I too have not found a way to reliably do fallback under the various
situations mentioned. Some are easy, others would be fairly hard if
not possible to get Asterisk to be able to detect. Then again,
fallback doesn't work well on some very expensive standard PBX's I've
supported.

If you haven't already thought about it, make sure to put a section in
your dial plan to allow users to force the system to use an alternate
provider -- like preface with a 6 uses provider 2 instead of the
default.

Not elegant, but at least it saves a little bit of the hassle on
support. If someone's call doesn't go through, they can force it to
the backup and try that. Either both won't work (which will help you
diagnose the problem when they page you on Sunday afternoon when
you're out with your kids), or if it does work at least they have a
way to make calls until you get a chance to login and fix the problem.

I have my dialplan setup so that the information on which provider to
use is pulled as a variable. Then I have an extension in there that
will allow you to flip to another provider with a simple phone call
from any extension. If need be, I can tell someone over the phone how
to do it so they can flip all of the dialplan information to the
backup provider so I don't have to rush over there as quickly if one
of them goes down.