> > If I change a DNS here in NZ, it is like injecting an agent into tip of a > > whales tail. It takes along time to propogate through the system. If I > > inject into the heart it is sent out a lot more quickly and spreads like > > a ripple from the centre of the pond, not from the edge. (some very mixed > > similes here). > > That's not how the DNS works. > > The DNS is organised as a heirachy purely for the purpose of splitting out > where answers come from into seperate entities, so that there is no single > central set of servers who are responsible for "all" answers.
sigh ... i didn't explain myself fully enough ... my concern is not with lookups but with changes in caches. I have had a number of situations where caching has resulted in DNS changes being a pain in the neck and not propogating correctly. This is especially true when working with overseas clients. To sit on the backbone in the USA gives me a quicker dissemination of changes to DNS entries. The lookups are heirarchical .. this I know, as you have mentioned you look up the closes and work outwards until you find it but caching sometimes mucks this up and so to make changes it is easier to start with the main servers and work down to the smaller servers, not the other way around. I am working with clients at a corporate level, closer to the main backbone of the naming structure, not small sites here. when a change happens it can ripple effects back to main servers in the USA. to start the ripple from a central position makes more sense if I am trying to get caches changed. DNS lookups can be cached, I have had it happen and trying to change those caches can be a right pain in the lookup.... Shane
