codns

codns

This code is borrowed from github.com/piger/nasello and adapted to easily work with consul.io.

A very simple DNS proxy server capable of routing client queries to different remote servers based on pattern matching.

The code is mostly based on Go-DNS examples.

Warning: this is alpha software and should be used with caution.

Getting Started

Running sudo ./codns you'll have a proxy dns running on port 127.0.0.1:53 TCP and UDP that resolves consul database at 127.0.0.1:8600 and the rest of the dns space.

Installing binary

curl https://raw.githubusercontent.com/jmcarbo/codns/master/bin/install | bash

Getting codns

The latest release is available at Github

Installing from source

You can install nasello from source:

go get github.com/jmcarbo/codns
go install github.com/jmcarbo/codns/codns

Configuration format

The configuration file is a JSON document which must contains a filters list with one or more pattern dictionaries; each filter must contain a FQDN DNS name as the pattern and a list of one or more remote DNS servers to forward the query to. For reverse lookups the in-addr.arpa domain must be used in the pattern definition.

The "." pattern specifies a default remote resolver.

Example

The following configuration example specifies three filters:

• *.consul will be resolved by Codns (localhost:8600)
• *.example.com will be resolved by OpenDNS (208.67.222.222, etc.)
• 10.0.24.* will also be resolved by OpenDNS
• all the other queries will be forwarded to Google DNS (8.8.8.8, etc.)

codns.json:

{
	"filters": [
			{
					"pattern": "consul.",
					"addresses": [ "127.0.0.1:8600" ]
			},
			{
					"pattern": "example.com.",
					"addresses": [ "208.67.222.222", "208.67.220.220" ]
			},
			{
					"pattern": "24.0.10.in-addr.arpa.",
					"addresses": [ "208.67.222.222", "208.67.220.220" ]
			},
			{
					"pattern": ".",
					"addresses": [ "8.8.8.8", "8.8.4.4" ]
			}
	]
}

License

codns is under the MIT license. See the LICENSE file for details.