On Mon, May 21, 2012 at 1:17 AM, Alan McKinnon <[email protected]> wrote: >> Slow connection. See my previous reply to the list. I'm using pdnsd, >> which can persist records and has every damn feature I wanted. >> > > Fair enough, but consider this: > > If your connection is slow, the only thing you speeded up is the DNS > lookups. Thereafter, everything else is still as slow as it ever was. > And if you feel the need to speed up DNS lookups then the odds are very > good that "everything else" is too slow i.e. not exactly usable. > > We get this a lot from our customers too, and the advise we give them > is to look closely at their traffic throttling. In almost every case > all UDP traffic has had the living crap throttled out of it somewhere > by folk that don't really think things through, severely affecting > dns and ntp as well as AV streaming. > > Throttled DNS rapidly gets out of hand, IIRC the last time we did some > measurements it only takes around 5% of dns lookups to go wonky for the > situation to rapidly spiral out of control - when dns fails the cache > will try a TCP lookup and that's like wading through molasses. > > Our advice to customers is to first unthrottle dns and ntp completely, > give it the highest possible priority (these are extremely light > protocols and seldom show up on the radar when you do this), and see > how that goes. > > It just seems to me that you *might* be trying a very unusual solution > for a problem that is better handled one layer lower down. >
Strictly speaking, my connection isn't too slow. I have a transfer rate of 64 K/s (might sound ridiculous to you, but this costs 18$/mo here). OpenDNS lookups from my connection take something like 300 msec+ and Google DNS lookups around 50 msec. I can obviously use Google DNS, but as I said earlier, OpenDNS gives me phishing protection and other that sort of stuff. And hence I must use a local cache. -- Nilesh Govindarajan http://nileshgr.com
