[CS-FSLUG] What if DNS goes down?

[sjm]

> You can get the machine, but I have no idea how to get the machine to 
> pass me the homepage of some site we all know is there.

Depends on the configuration of the sites.  Some you might be able to 
use the http://ip.add.re.ss/site.name.tld/, but usually it's not done 
that way for security reasons.  There's no good way to do it that I know of.

> I've used Bind9 and DJBDNS nameserver caching before. But from reading 
> the documentation, what little I understood, it seemed to indicate the 
> server would periodically renew the cache in case based on something to 
> do with keeping up to date with updated address matching on the zone and 
> root servers.

It all has to do with the TTL value set at the authoritative name server 
for the site.  The caching server will not query again until the TTL 
value has counted down to zero.

sjm



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