DNS Cache, database backends...

[James Raftery]

On Wed, Feb 07, 2001 at 10:55:57AM +0000, Jim Reid wrote:
> Some computers are bad at timekeeping. 

Sure, but some computers are bad at disk I/O, some bad at shuffling
around large amounts of data in real memory. They still use software
that calls upon them to do these things.

> I can envisage clueless DNS admins copying these
> files from server to server and then whining because the restored
> caches are not the same because the server's clocks don't keep the
> same time.

Yep, I could see that too. The answer to them is simple; tough. If they
want time-based operations to work correctly they need to give their
systems a cohesive view of time.

> And to repeat what I said earlier, the easy way to solve
> this "problem" is simply to leave the name servers alone and only stop
> and start them when it's really necessary: for example when installing
> new name server software.

I agree. However I also think that the ability to prime ones cache upon
startup either from a dump of some preexisting cache or from a list of
desired cache contents I make up myself would be a useful feature. Even
with the best administration nameservers need to be stopped from
time-to-time. Not having to lose the contents of the cache would be 
neat. It's not essential, by any means, but I think it would be kinda
groovy.

> This discussion about preserving caches is just silly. It's a bit like
> expecting the entire contents of your computer's RAM or the state of
> every CPU register to be preserved after the system has been power
> cycled. Sure it could be done, but what's the point? Really.

My laptop can "suspend to disk" :-)


ATB,

james
-- 
James Raftery (JBR54)
  "It's somewhere in the Red Hat district"  --  A network engineer's
   freudian slip when talking about Amsterdam's nightlife at RIPE 38.