Multiple ISPs on one hostname

[Pete Tenereillo]

David, regardless of what you do or what you buy, there are scenarios where
a given user may get "stuck" on the bad link, but it's hard to do much
better than what can be achieved by returning multiple A records (one for an
IP from each ISP in your case) and allowing caching nameservers to RR (and
that's free). Of course that does not meet your stated requirement of using
the links in a purely active/backup fashion. The "bouncers" can be
configured for pure active/backup, but will set you back $10-30K (you will
want 2 units for redundancy), and most of what you are paying for scarcely
works as advertised in those. You might find some of the information here
useful:

http://www.tenereillo.com/Papers.htm


Pete.

----- Original Message ----- 
From: "David Jacoby" <dj at outpost24.com>
To: <bind-users at isc.org>
Sent: Sunday, July 04, 2004 11:26 PM
Subject: Multiple ISPs on one hostname


> Hi!
>
> I have a little problem, i have 2 Internet connections from two
> completely different ISPs
> on two completely different subnets, i want to use one of them as a
> backup connection
> if the first one dies.
>
> Ive searched the net and asked people and all they can say is use a
> "proxy"/"Bouncer" or
> the "round robin" method, but they are not 100% stable.
>
> If i use the proxy/bouncer there might be a problem if the actual
> proxy/bouncer dies, and with the
> "Round Robin" technique it might be a problem for visitors who have a
> long TTL in their DNS CFG.
>
> Is there someone here who knows some other technique i can use or have
> some additional information
> about this.
>
> Thanx alot!
>
> -- 
> Best regards,
> David Jacoby
> Security Analysist
>
> Outpost24 Security Team
>
>
>