My kingdom for a working DNS

Earl Moore lists at enfuego.us
Thu Feb 5 14:08:22 UTC 2004


> I noticed all posts talked about caching DNS. I
> haven't got the faintest idea of what it really is. I
> figure it's a system which checks with an external DNS
> (maybe the one in my resolv.conf now) and makes a copy
> of the whole list on my computer. Then I should point
> resolv.conf to 127.0.0.1. Is this right?

Mostly right. ;)  It checks locally to see who has an address, if its not
found it goes to the dns root servers to figure it out.  It then caches the
information on a particular address for an amount of time specified by the
dns server that hosts that domain.

>
> I have a few questions about this:
>
> 1) Does this speed up my internet connection?

I wouldn't think that it would make a noticeable difference.

> 2) Is it reliable? Supposing the DNS table changes,
> does the copy on my HD change the first time I connect
> to the net, or is there a manual procedure to update
> it?

There is a lag time between an address change and when your local cache
expires but this is the same as if you used your isp's dns.

> 3) Brian Fahrlander said "Keep things simple to get
> the functionality, THEN improve it to make it easier
> on all those involved." Does that mean that caching
> DNS reduces the load on the net?

I'll let him answer that!

Good luck!






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