Caching only Nameserver?

[Kevin Darcy]

buedi at gmx.net wrote:

> On 15 Jun 2000 10:36:48 -0700, Barry Margolin <barmar at genuity.net>
> wrote:
>
> >>thought a caching only Server holds a database with all the IP <->
> >>names?? I think I made a mistake in my configuration, read different
> [...]
> >Named keeps the cache in memory.  Restarting named wipes its memory, so the
> >cache is gone.
> So my configuration seems to be correct :-)
> Say... does all Name Servers on the Internet work like this? Cache the
> data only in memory?
> If (hypotetically) all the Name Server´s in the I-Net where rebootet
> at the same time... the request for a specific domain could take hours
> till it is resolved... then a nslookup request would run across the
> Internet till he finds the Server who holds the domain?

I doubt that it would take "hours". If all of the machines were back up and
running in say, 30 minutes, then it would take at most 30 minutes + (n
* average query/response time) where "n" is the number of domain levels that
need to be queried to get the answer, including the root (assuming that all of
the servers at each level are responding properly). So, for "www.foo.com", it
would require a maximum of 4 queries -- one to a root server, one to a
"com" server, one to a "foo.com" server, and one to a "www.foo.com" server (if
it were a separate zone for some reason). All of this querying is likely to
take less than a minute.


- Kevin