Forwarding to two servers

[Kevin Darcy]

On 8/6/2010 1:05 PM, CLOSE Dave (DAE) wrote:
> Joseph S D Yao wrote:
>
>    
>> If you have two forwarders, as you listed, your server will try to
>> forward first to one and then to the other.  If it gets any answer at
>> all from one - even an error answer - it will not try the other.
>>      
> So forwarding works exactly the same as listing both servers in
> resolv.conf? That behavior is exactly what I'm trying to avoid.
>
>    
>> There are many ways to try to cascade name servers and try them one at a
>> time.  By the good design of BIND, none of them work.
>>      
> If BIND won't do the job, can you suggest another server that will? I
> can't be the only one wanting to do something like this.
>
>    
>> On your new server:
>>
>> zone "." { type hint; file "root.hints"; };
>> zone "private.example.com" { type forward; forward only;
>>      
>   >    forwarders { private.domain.server.IP; }; };
>    
>> and put the IP address for this name server and no other in your
>> /etc/resolv.conf.
>>      
> Ah, that might work -- in other circumstances. I understand the basic
> idea to be using separate zones to force forwarding to different servers
> for different domains. Did I understand correctly?
>
> But an unfortunate characteristic of my PRIV server is that it doesn't
> use /any/ domain. It only resolves simple, unqualified names like HOST1.
> This was clearly a mistake in design (from before my time), but I have
> no ability to change it (in the next five years, anyway).
>    
Ah, so you want to implement something new, but not willing to fix the 
old broken design which is incompatible with what you're trying to 
implement. Gotcha.

The only halfway-reasonable way I see for your to work around this 
broken design is to define each of those "unqualified" names 
individually in your nameserver config, e.g.

zone "HOST1" {
     type master;
     file "HOST1";
};

and hope they don't change too often.

                                                                         
                                                         - Kevin


                                                                         
                                                                         
- Kevin