[SATLUG] Home DNS Caching

[Samuel Leon]

Robert J Hewitt wrote:
> Sorry to jump in on this but cn you run a home DNS server on a system
> running IPcop (my firewall) and if I am not running a web server,
> mailserver or any other type but just a home network is the DNS worth
> the extra load on a system really
>
>
> RObert
> On Fri, 2007-08-03 at 11:53 -0500, Daniel J. Givens wrote:
>   
>> Sean Carolan wrote:
>>     
>>> Do any of you run your own DNS server on your home networks?  If so do
>>> you find this beneficial?
>>>       
>> Yes, I do. I use it for more than just caching. I do a good deal of web
>> development and it helps to be able to create new hostnames for virtual
>> hosts. Also, I have an internal mail server, so having the MX record is
>> handy. The speeds are better for me when it comes to resolution, but
>> that largely depends on your ISPs nameservers. I have a crappy ISP and
>> their nameservers are slow when they aren't down.
>>
>> In all honesty, setting up a BIND caching nameserver is typically no
>> more than installing the package from your distro and making sure it's
>> running. If you have a host based firewall on the to-be server, then you
>> have to open up the ports on the box (TCP/UDP 53). Other than that,
>> either change your workstations to point to the new server or update
>> your DHCP settings. Easy as pie.
>>     
>
>   

Ipcop comes with dnsmasq  which is a dns and dhcp server in one.  
However it is not a full dns server.  It cannot look up dns request.  It 
only caches requests that were forwarded to your isp dns server.  To 
enable the caching feature of dnsmasq, it looks like to have to add 
"nameserver 127.0.0.1" to /etc/resolv.conf: Some info 
<http://ubuntu.wordpress.com/2006/08/02/local-dns-cache-for-faster-browsing/>

A full dns server like BIND will not rely on your isp's dns server.  It 
will look up addresses from the known public dns servers.  This can 
sometimes be slower than your isp's dns, but you have the benefit  of 
never being without a dns server (RR's dns was just down for a few hours 
like a month ago right?)

The typical requirements for BIND on a small LAN is like 2mb of ram and 
almost no cpu.


Sam