[dns-operations] cache and subnet option
dns at fl1ger.de
Thu Apr 20 01:43:35 UTC 2017
On 19 Apr 2017, at 20:16, Randy Bush wrote:
> dear lazynet,
> caching resolver R serves clients on subnets S0 and S1. a device on S0
> queries for wanna.know. R queries for the data using the subnet option.
> a device on S1 then queries for wanna.know. does R respond with the
> cached data from the S0 query, or issue a new query with the S1 subnet
If S0 doesn't enclose S1 it has to issue a new query and cache that with
the appropriate subnet.
> [ to my naïve eye, issuing a second query would seem to have, shall we
> say, interesting scaling properties ]
It does and that is why it usually better to get the distribution effect
by placing resolvers near the edge of the network.
More information about the dns-operations