Pgwrr is a pipe backend for PowerDNS which can geographically locate the incoming DNS request, and load balance it with the weighted round robin algorithm.

pipe-command=/usr/bin/pgwrr -g geoip2.mmdb -z zones.yml -s sites.yml

Three databases are required:

• GeoLite2 or GeoIP2 City database from MaxMind
• zones.yml file which defines the mapping between countries and arbitrary geographical zones
• sites.yml file which holds the DNS records for given zones with weights

'default': eu        # Default zone for the world is "eu"
'US':
  'default': us-east # Default zone for the US is "us-east"
  'CA': us-west      # Map California to "us-west"
'CN': asia           # Map China to "asia"

'*.example.com':
  IN:
    A:
      content:
        ttl: 300
        default:
          10.0.0.1: 100 # default for all zones
        us-east:
          10.0.0.2: 30  # 30% of requests
          10.0.0.3: 70  # 70% of requests
        us-west:
          10.0.0.4: 20  # 20% of requests
          10.0.0.5: 20  # 20% of requests
          10.0.0.6: 60  # 60% of requests

In the above example, any request going to *.example.com from

• California will resolve to either 10.0.0.4, 10.0.0.5, or10.0.0.6
• the rest of the US will resolve to 10.0.0.2 or 10.0.0.3
• the rest of the world will resolve to 10.0.0.1

For best performance it is highly recommended to specify a zone for every single country using the ISO 3166-1 alpha-2 country code. If you want to have country regions in different zones, you must use the ISO 3166-2 country subdivision code under the country code. You must also specify a default zone both for countries and, if applicable, subdivisions in case GeoIP does not return a country or subdivision code.

It would be best if this plugin is used only when needed, as in only for domain names that you actually can load balance. This is easy to set up in PowerDNS with:

launch=pipe,bind
pipe-regex=^filter_regex;(A|AAAA|ANY)$
pipe-command=/usr/bin/pgwrr -g geoip2.mmdb -z zones.yml -s sites.yml

The above configuration will use the pipe backend only if it passes the pipe-regex. In all other cases it will use the bind backend.

sh geoip/download.sh

export PYTHONPATH=$(pwd)

nosetests

sniffer

vagrant up