[scale] How to scale Docker containers in production

So I recently discovered this awesome tool, and it says

Docker is an open-source project to easily create lightweight, portable, self-sufficient containers from any application. The same container that a developer builds and tests on a laptop can run at scale, in production, on VMs, bare metal, OpenStack clusters, public clouds and more.

Let's say I have a docker image which runs Nginx and a website connects to external database. How do I scale the container in production?

You can try Tsuru. Tsuru is a opensource PaaS inspired in Heroku, and it is already with some products in production at Globo.com(internet arm of the biggest Broadcast Television Company in Brazil)

It manages the entire flow of an application, since the container creation, deploy, routing(with hipache) with many nice features as docker cluster, scaling of units, segregated deploy, etc.

Take a look in our documentation bellow: http://docs.tsuru.io/

Here our post covering our environment: http://blog.tsuru.io/2014/04/04/running-tsuru-in-production-scaling-and-segregating-docker-containers/

Deis automates scaling of Docker containers (among other things).

Deis (pronounced DAY-iss) is an open source PaaS that makes it easy to deploy and manage applications on your own servers. Deis builds upon Docker and CoreOS to provide a lightweight PaaS with a Heroku-inspired workflow.

Here is the developer workflow:

deis create myapp                      # create a new deis app called "myapp"
git push deis master                   # built with a buildpack or dockerfile
deis scale web=16 worker=4             # scale up docker containers

Deis automatically deploys your Docker containers across a CoreOS cluster and configures the Nginx routers to route requests to healthy Docker containers. If a host dies, containers are automatically restarted on another host in seconds. Just browse to the proxy URL or use deis open to hit your app.

Some other useful commands:

deis config:set DATABASE_URL=          # attach to a database w/ an envvar
deis run make test                     # run ephemeral containers for one-off tasks
deis logs                              # get aggregated logs for troubleshooting
deis rollback v23                      # rollback to a prior release

To see this in action, check out the terminal video at http://deis.io/overview/. You can also learn about Deis concepts or jump right into deploying your own private PaaS.

Openshift guys also created a project. You can find more information here, try test container and detailed info here . The only problem is the solution is Redhat centric for now :)

Take a look also at etcd and Consul.

One option not mentioned in other posts is Helios. It is built by spotify and does not try to do too much.

https://github.com/spotify/helios

Panamax: Docker Management for Humans. panamax.io

Fig: Fast, isolated development environments using Docker. fig.sh

While we're big fans of Deis (deis.io) and are actively deploying to it, there are other Heroku like PaaS style deployment solutions out there, including:

Longshoreman from the Wayfinder folks:

https://github.com/longshoreman/longshoreman

Decker from the CloudCredo folks, using CloudFoundry:

http://www.cloudcredo.com/decker-docker-cloud-foundry/

As for straight up orchestration, NewRelic's opensource Centurion project seems quite promising:

https://github.com/newrelic/centurion

A sensible approach to scaling Docker could be:

1. Each service will be a docker container
2. Intra container service discovery managed through links (new feature from docker 0.6.5)
3. Containers will be deployed through Dokku
4. Applications will be managed through Shipyard which in its turn is using hipache

Another docker open sourced project from Yandex:

• cocaine

Have a look at Rancher.com - it can manage multiple Docker hosts and much more.