Why we need Container Orchestration

• We don't like pets in server farms :)
• We want zero downtime
• We want auto-scaling
• We want to go across different cloud providers

Container Orchestration Options

• Docker Swarm
• Kubernetes
• Mesos Marathon
• Cloud Foundry Diego
• Apache Aurora
• Amazon ECS
• Azure container Service

As you could guess, it becomes difficult to choose one. So we thought of taking one Real World App and deploy it in different orchestration engines. For now we would look into Docker Swarm, Kubernetes and Mesos marathon.

What is needed to do the Container Orchestration

Multiple Nodes to be part of a cluster

Unique ID/Token to bind all the nodes in a unique cluster

Container Engines

• Docker
• Rkt

Single source of truth about configuration for nodes

• Key-Value Store like etcd, consul

Network for containers of different nodes to talk to each other

• Some form of Overlay network like VxLAN.
• With possibility to plug different neworking solution like Calico.

One or more cluster master to manage the cluster and schedule the jobs/tasks

Scheduler to schedule the containers on nodes based on

• Constraints, like run the container where SSD storage is available
• Affinity

Service discovery within the cluster

• Internal DNS server
• Through environment variables
• Load balancer, HA proxy

Access to external shared storage

• Volume plugins

Examples

We are going to look at two examples :-

dockchat

This is a simple example, which I borrowed from from DockerCon EU tutorial. In that tutorial, the steps are given to orchestrate the simple chat application using Docker Swarm. Here would take that same app and deploy it using Kubernetes and Mesos.

• Swarm

  • Docker Compose - Single system
  • Docker Compose - Swarm Cluster
  • Swarm cluster with Interlock
  • Swarm cluster with Overlay network

• Kubernetes

• Mesos

Magento

We thought a real world e-commerce platform would be a nice and came across Magento. While doing some browsing we came across this blog post to deploy Magento2 on Tutum., which gave us good reference.

So first we would deploy Magneto on differnet orhestration engines and then experiment with features like replication, auto-scaling etc.

TDB

Credits

• Nicola Kabar putting down (dockchat)[https://github.com/nicolaka/dockchat] for DockerCon EU'15 Tutorial

• Mark Shust for providing Magento2 Docker Compose file https://github.com/mageinferno/magento2-docker-compose