injecting a temp entry into dns cache

[Phil Mayers]

On 02/02/2013 09:41 PM, Veaceslav Revutchi wrote:
> There is a credit union website that our users access from work and
> their dns has been broken for the past few days where the www. version
> works,  but the plain name (without the www.) points to some old IP
> that's not responding. Tried to call them and all I got was that they
> know they have some kind of problem, but they ask users to type www.
> in their browser until it's resolved.
>
> In situations like this I would like to be able to inject an entry
> into the cache on our recursive resolvers and point it to the correct
> IP until the domain
> owner fixes the problem (poison my own cache so to speak). Is this
> something that can be done with bind without having to create a zone
> for the broken domain and make our servers act as authoritative for
> it?

You can do this with RPZ. Simply put:

thebrokensite.org.your.rpz.zone. IN A working.ip.add.r

...into the RPZ zone. This will leave names *under* that zone alone. 
I've used RPZ this way a couple of times to fix temporary problems, but 
you need to be aware of the hole you can dig yourself if you end up 
having to do this permanently.