default local DNS caching name server

P J P pj.pandit at
Sat Apr 12 11:56:58 UTC 2014

> On Saturday, 12 April 2014 4:55 PM, William Brown wrote:

> This isn't how DNS works ..... You populate your cache from the ISP, who
> queries above them and so on up to the root server. 

  Hmmn. There are two ways a local resolver can be configured. One is it contacts root servers and builds its cache from their responses. That's recursive name resolution. And second is it acts like a stub resolver and forwards client queries to another recursive resolver.

N-DJBDNS supports both these options. Maybe you could install it and see for yourself.

   try ->  # yum install ndjbdns

> I should clarify. I cache the record from the office, and
> it resolves differently externally. When I go home, it no longer
> resolves to the external IP as I'm using the internally acquired record
> from cache. 

  No. Your address does not resolve to a public internet address, but resolves to an internal company specific address. And when you come home, your domain still resolves to the _same_ internal address, but you are unable to connect to it because you are outside of the office network. 

Try connecting over VPN connection from home.

> A local cache will help you with 1 "sometimes" provided you get the
> first record back once. 
> It won't prevent the second or third as you will just cache the
> incorrect data instead (Provided you clear cache on network change, this
> isn't a problem ... it just means you hold onto bad data for that
> session for longer, which creates other issues.)
> I personally am actually against DNS cache on systems as it tends to
> create more problems than it solves.

  Maybe you could try N-DJBDNS -> # yum install ndjbdns


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