Re: Relay to DNS Server ?

[Akao <technique@akao.fr>]

Mark Anacker wrote:

> Antony Stone wrote:
>
>> On Wednesday 16 June 2004 2:53 pm, Patrick Leslie Polzer wrote:
>>
>>
>>> On Wed, 16 Jun 2004 15:31:37 +0200
>>>
>>> Akao <technique@akao.fr> wrote:
>>>
>>>> Is it possible to use netfilter rules to "relay" clients DNS 
>>>> requests ?
>>>
>>>
>>> Masquerading does that, but you must allow packets to port 53 
>>> tcp/udp to
>>> pass through to your ISP's DNS servers and their related packets back.
>>
>>
>>
>> This is a completely correct and accurate answer to your question, 
>> however I think you would get much better performance for very little 
>> effort if you set up a simple caching-only name server somewhere on 
>> your network (possibly even on the firewall itself, but don't tell 
>> anyone I suggested that :)
>>
>> Regards,
>>
>> Antony.
>>
>
> You might want to run a DNS cache like dnsmasq on the firewall box, 
> then use a REDIRECT or DNAT rule to grab client's requests and force 
> them into the cache.  That way, the client's don't have to change 
> their DNS server list, and you get the benefits of caching.
>
Ok, thanks for your answers.
 I managed to complete clients DNS requests with masquerading. I will 
look for a dns cache as you adviced me.

Thanks again for your answers.

Axel