DNSControl

Simplified control over DNS routing in JAVA

When you need more control on which DNS servers to use in Java for certain hosts or domains.

Quick startup

Create a DNS Control configuration file as such:

# Selection order is more specific wins
# For example, if you have a host, domain, and default override, they will be processed in that order.
# The left hand side is the destination to override, the right hand is the list of dns servers to use.
# Left hand entries should be unique, one entry per destination.
# Don't need to suffix your entries with "." dot, this is implied, meaning, default domain will not be appended.

# Setup default DNS servers, this is optional.
# If not defined, the current host DNS servers will be used if unset (i.e. resolv.conf).
.=10.0.0.1,10.0.0.2

# Override DNS lookups for specific hosts
www.openpojo.com=10.1.1.1

# Override DNS lookups for whole domains (starts with "." dot),
# This will override lookups for *.openpojo.com (i.e. some.host.openpojo.com)
.openpojo.com=10.0.2.2

# Suppress any queries that you'd like to never resolve
hiddenhost.openpojo.com=

# Finally if you want to use your current system's DNS servers without having to know the entries.
unchanged.resolution.openpojo.com=SYSTEM

startup your JVM passing NameService provider as well as DNS routing file

java -Dsun.net.spi.nameservice.provider.1=dns,dnscontrol \
     -Ddnscontrol.conf.file=/path/where/dns_control_file

If you have a hosts file you'd like to also use you may use the jdk.net.hosts.file property and add it to your startup parameters

java -Dsun.net.spi.nameservice.provider.1=dns,dnscontrol \
     -Ddnscontrol.conf.file=/path/where/dns_control_file \
     -Djdk.net.hosts.file=/path/where/hosts_file

Notes:

1. The default value for dnscontrol.conf.file is /dnscontrol.conf on root of the classpath.
2. The Hosts file is the highest priority when it comes to resolution.

Environment

Currently DNSControl runs on Java 1.7 & 1.8.

Builds on the functionality provided by dnsjava.