MontyRee wrote: > Hello, list. > > > I have some questions about RTT(Round Trip Time) related. > please let me know. > > > -.I have operated cache only bind dns server. > but, where can I find RTT information at my DNS Server? > If you have a sufficiently-modern version of BIND, you can dump its database (via rndc dumpdb), and in the dump file there will be a section that looks like this: ; ; Address database dump ; ; ns6.mesdns.net [v4 TTL 3295] [v6 TTL 3295] [v4 success] [v6 nxrrset] ; 66.46.181.244 [srtt 31] [flags 00000000] ; ns3.radicalties.com [v4 TTL 72299] [v4 success] [v6 unexpected] ; 64.38.195.231 [srtt 55050] [flags 00000008] [ttl -524]
, and, typically many more entries. > -. If I operating the global web site, is it better to setup lots of dns > servers as many as possible(max 13) > around the world to improve the response time? > > It might help a bit, yes, but typically in a global-website context, the main delay consists of fetching the actual web content, with the DNS lookup being only a small fraction of the time. You might want to focus on CDN (Content Delivery Network) technology more than trying to optimize your DNS lookups. Sometimes DNS and CDN technologies are rolled into one package anyway (at least, I know this is true of some of Akamai's offerings), so you may end up not having much flexibility on the DNS side of things anyway. - Kevin
