3 Feb 2016 in etcd, CoreOS, Overview

etcd on CoreOS

In my last post, we learnt about CoreOS installation on AWS EC2 instances. Specifically, we saw how to create a CoreOS cluster with three nodes and connect to nodes from terminal window.

One of the main building blocks of CoreOS is etcd, a distributed key-value store. When applications run on a cluster, accessing application config data in a consistent manner is a problem, since using the underlying system’s file system is not feasible.

If you want to build a failsafe cluster, application config needs to be available across the cluster. etcd solves this problem. Think of it as a file system available across all the cluster nodes. See my previous post that discusses etcd in more detail.

In this post, we’re going to look at how to use etc in real-life scenarios.

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29 Jan 2016 in Series: CoreOS Overview, CoreOS, Overview

CoreOS Overview, Part One

This post is available in: Chinese

CoreOS is an important part of many container stacks. In this series of posts, we’re going to take a look at CoreOS, why it’s important, and how it works. If you don’t know anything about CoreOS already, don’t worry. We start at the beginning.

The Basics and How CoreOS Is Different From Other Linux Systems

CoreOS is designed for security, consistency, and reliability.

  • Automatic CoreOS updates are done using an active/passive dual-partition scheme to update CoreOS as a single unit, instead of using a package-by-package method. We go over this in detail later.
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28 Jan 2016 in Deis v1 PaaS, DigitalOcean, Tutorial

How To Set Up a Deis Cluster on DigitalOcean

In a previous post, we used Rigger to deploy Deis on DigitalOcean. In this post, we take a different and more detailed approach.


Deis is an open source private Platform as a Service (PaaS) that simplifies deploying and managing your applications on your own servers. By leveraging technologies such as Docker and CoreOS, Deis provides a workflow and scaling features that are similar to that of Heroku, on the hosting provider of your choice. Deis supports applications that can run in a Docker container, and can run on any platform that supports CoreOS.

Read on to learn how to set up your own 3-machine Deis cluster on DigitalOcean.

Note: This tutorial is based on the v1.9.0 release of Deis.
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22 Jan 2016 in CoreOS, AWS, Tutorial

Production CoreOS on AWS EC2

In previous posts, we learnt about installing CoreOS on VirtualBox to get you up to speed with cloud-config files and the general installation process. We also learnt about various CoreOS components, such as systemd, fleet, and etcd. However, if you want to run CoreOS in production, there are several other things to take care of: security, system failures, cluster scaling, and remote access, to name just a few.

CoreOS ensures scalability and failsafe clustering out of the box. And cloud deployment is the way to go if you want scalable, secure infrastructure. But how do you get a CoreOS cluster running in the cloud? There are several related questions. Do you need to install CoreOS on all the nodes separately? What about the cloud-config files? How does a cluster get defined logically?

In this post I’ll go over the CoreOS installation process and hopefully answer these questions for you.

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20 Jan 2016 in Roundup, Containers

Popular Off-The-Shelf Container Tooling

With the rise of Infrastructure as a Service (IaaS), more and more people are turning to containers (and microservices) as new models of application development that take full advantage of everything the cloud has to offer.

These models offer many benefits over old ways of working, but bring with them a unique set of new challenges: service discovery, infrastructure management, cluster orchestration, monitoring, container-centric continuous integration, to name just a few.

Thankfully, there are a number of popular off-the-shelf tools that can help you with these challenges.

We'll take a look at a few of those tools in this post.

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