PowerDNS

PowerDNS [1] is the DNS server we use for geographic DNS balancing, and possibly "normal" authoritative DNS in future as well. This page explains configuration.

Global configuration

It's best to bind PowerDNS to a specific IP, instead of INADDR_ANY. To do that, put:

local-address=IP
query-local-address=IP

A backend like geobackend can't make use of caching, since returned results will be different depending on "who's asking". Therefor, disable caching:

query-cache-ttl=0
cache-ttl=0
negquery-cache-ttl=300

If just geobackend is used, multithreading is unneccessary, and may even impact performance. Make pdns singlethreaded with:

distributor-threads=1

In geobackend itself, there are no wildcard records, so pdns shouldn't have to check for them:

wildcards=no

Running privileged is unnecessary (of course make sure these user/group exist):

setuid=pdns
setgid=pdns

Launch the backend that will be used, in the specified order:

launch=geo