Anton Aylward wrote:
Greg Freemyer said the following on 01/03/2014 10:20 AM:
On Fri, Jan 3, 2014 at 10:13 AM, James Knott
wrote: Anton Aylward wrote:
From my POV having an old or tiny box dedicated to DNS with a couple of gigs of memory[1] with a -ing cache and a -ing long timeout will 'outperform' all of the above after a couple of days, provided I don't turn it off at night.
Actually, the time to live value in the returned DNS reply will limit any caching. I just did one test for Yahoo and it showed 34 seconds. Another one showed 3 min 2 sec, so upstream caches will return a varying TTL depending on when they obtained the record. Those times are nowhere near "overnight".
I had no idea TTLs were so short these days. When I was admin'ing DNS 15+ years ago, a week was a very common TTL (time-to-live).
+1. My Albitz&Liu talks of a default of 85400 seconds, which is 24 hours which *IS* overnight!
Why should a site have such short TTL? The only justification I can think of is that they are implementing Round Robin DNS that way.
And that's a poor justification. Maybe have a look at 'rrset' in the bind manual. -- Per Jessen, Zürich (7.2°C) http://www.hostsuisse.com/ - dedicated server rental in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org