Config check for box swith two nics

[Rick Stevens]

Felipe Alfaro Solana wrote:
> On 18 Mar 2005, at 21:26, GPL wrote:
> 
>> I am working with a box that has two nics. I want the PUBLIC interface
>> to use two of my external DNS servers and the INTERNAL interface to
>> use two of my internal DNS servers. This is not a router as I have not
>> turned routing on. Not sure my resolv.conf is right. When I try to
>> ping an internal host by just host name and FQDN it fails. Fine by IP.
>> Ping by name on Internet side fine.
> 
> 
> Name resolution is jus that: name resolution... when you try to resolve 
> a name, you don't know beforehand what interface you should use, since 
> you only know the host name. When you want to resolve a name, you ask a 
> name server, but you can't distinguish between internal or external 
> queries.
> 
> AFAIK, what you want to do is impossible.

You can't direct a DNS query to a specific DNS server, that's true.
You can, however, put multiple DNS servers in your /etc/resolv.conf
file.  I'd suggest you put the external DNS servers in first, and your
internal server in last.  If the name resolution doesn't happen on one
of the external servers, it'll revert to the internal server.

BTW, only the first three DNS servers in /etc/resolv.conf are used.
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