Yura Pismerov wrote: >> Sure, but this adds undue load on my nameserver, and those of my >> customers for zones which I know will *never* change. >> > > Ok, now I wee I misunderstood you, so never mind my comment about > Dynamic DNS. > Now, what do you mean by load on your nameserver ? We were talking > about servers hosted at Tucows, right ? > Or you are talking about dedicated DNS box that is allocated at our > sites and that you "own" exclusively ? Please clarify. > As for the global vs. record TTL, this is how current version of the > product works. > The record based TTL must be assigned in any case, so no options here. > As for the ability to change it to a larger value, I can't comment it > - Bruce may want to do it.
This message, frankly, scares me. Please don't take offense at that though, but first, stop and think about how DNS works. Lets say I run a small company (I do), and lets say I have poor internet connectivity, high latency (I don't, although my laptop does when I'm on the road). Now, every single time I, or one of my users, hits http://www.mycompany.com/ the machine needs to resolve the IP. The same happens when I hit http://www.microsoft.com/ or any other site in the world. Prior to W2K there was no functional caching beyond application level DNS caching. This means every time you close your browser and open it again, all is forgotten. Even with W2K, every PC in the network needs to do DNS resolution for itself. The solution is to install a caching only DNS server (About 15 mouse clicks for NT or W2K), point my users to that server (about 8 mouse clicks, plus you have to type an IP, if you use MS DHCP), and have that server cache DNS lookups. With a caching DNS server enabled, the first person to hit www.mycompany.com would ask my DNS server, and my DNS server would look it up and return the result. From then until the end of the TTL period, queries for www.mycompany.com can be handled by my DNS server, instead of going out to the world. In W2K and up, there is a local DNSCache as well, it does the same thing as running a caching DNS server on every machine, it remembers IPs for the duration of the TTL. A short TTL means that my machine (be it my W2K/XP laptop, or my DNS caching server) has check the DNS records every 5 minutes. Sure DNS lookups are small and fast on your average dialup or broadband service, but they're killer in a CDPD wireless environment, satellite receiver, or basically any time where you have high latency, high packet loss, or both. -- Dave Warren, Email Address: [EMAIL PROTECTED] Cell: (403) 371-3470 Fax: (403) 371-3471 Toll free: (888) 371-3470 Vonage: (817) 886-0860 ICQ: 17848192 AIM: devilspgd Yahoo!: devilspgd MSN/PASSPORT: [EMAIL PROTECTED]
