mailing list archives
Re: DNS caches that support partitioning ?
From: Mark Andrews <marka () isc org>
Date: Mon, 20 Aug 2012 07:37:31 +1000
In message <DDF607B5-415B-41E8-9222-EB549D3DBB0C () semihuman com>, Chris Woodfiel
What Patrick said. For large sites that offer services in multiple data =
centers on multiple IPs that can individually fail at any time, 300 =
seconds is actually a bit on the long end.
Which is why the DNS supports multiple address records. Clients
don't have to wait a minutes to fallover to a second address. One
doesn't have to point all the addresses returned to the closest
data center. One can get sub-second fail over in clients as HE
As for the original problem. LRU replacement will keep "hot" items in
the cache unless it is seriously undersized.
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742 INTERNET: marka () isc org