docker-bg

An attempt of Blue Green deployment using Docker.

About

This POC is powered by the following tools:

• Fig: a tool used to manage an application in distributed containers.

See: http://www.fig.sh/

• Nginx: an HTTP and reverse proxy server.

See: http://nginx.org/

• Consul: a tool for discovering and configuring services in your infrastructure.

See: https://www.consul.io/

• Consul-template: a daemon used to populate values from Consul on your filesystem.

See: https://github.com/hashicorp/consul-template

• Registrator: a tool that automatically register/deregister Docker containers into Consul.

See: https://github.com/gliderlabs/registrator

How to

Pre-requisites

Ensure you have Docker installed.

Install fig:

$ sudo pip install -U fig

Update the fig.yml file and replace ROUTABLE_IP with a routable IP address (use your main interface IP address).

Build the 2 sites images:

$ docker build -t sitea siteA/
$ docker build -t siteb siteB/

Let's play

Start the Nginx + Consul + Registrator stack:

$ fig pull & fig build
$ fig up -d

Start a "v1" container:

$ docker run -d -e "SERVICE_NAME=my_service" -e "SERVICE_TAGS=my_tag" -p 80 -d sitea

Point your browser at http://localhost to see the result.

Next, start a "v2" container:

$ docker run -d -e "SERVICE_NAME=my_service" -e "SERVICE_TAGS=my_tag" -p 80 -d siteb

Point your browser at http://localhost to see the result, you should now be load balanced between the 2 versions.

Stop your v1 container and enjoy a smooth BG deployment :)

Bonus

Access the Consul UI via http://localhost:8500