A small daemon to keep a Bind DNS server in sync with containers created in Docker Swarm.

To use:

1. copy a rndc.key file containing the DDNS key from bind in this directory
2. customize the build.sh file to set the right Docker tags for your environment
3. run build.sh to build and push the Docker image containing the RNDC key (do not push to the public docker hub!)
4. customize the start.sh script: set the Swarm manager location, volume path and image name
5. run start.sh and enjoy your fully qualified container names

start.sh will run swarm-dns in a container.

Launch containers by giving them hostnames (the -h option of docker run).

Please note:

This script is work-in-progress and should be used with caution. You will need to modify main.py to set the DNS server IP and domain to use for the containers.

Since Docker reports only the ID of the container in the event stream, swarm-dns needs to keep the association between ID, IP and hostname, so that it can remove the entry from the DNS when the container is destroyed. This means that swarm-dns has state and it makes it much more complex and unreliable. The state can go out of sync if events happen while swarm-dns is down or if the state file is lost.

Nothing should prevent swarm-dns from working with a Docker Engine instance instead of a full Swarm.

Pull requests are more than welcome!