Scott's Weblog The weblog of an IT pro specializing in virtualization, networking, open source, and cloud computing

Retiring the Rockstar: A Counterpoint

“You’re a rockstar!” Chances are, you’ve either a) been told this as a compliment for some work you’d done; b) heard this told to someone else for some work they’d done; or c) told someone this for some work they’d done. If you said this to someone else—I just told someone this quite recently—chances are also very likely that you had nothing but positive intentions behind this statement and your goal was to compliment them on what you saw as outstanding work. But is “rockstar” the wrong term to use? And if so, what is the right term?

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A Quick Update on OpenStack Congress

OpenStack Congress, a project aimed at providing “policy as a service” for OpenStack clouds, is a project I’ve had the privilege of being involved in from very early days. I first mentioned Congress almost a year ago, and since then the developers have been hard at work on the project. Recently, one of the lead developers posted a summary of some pretty impressive performance improvements that have been made with Congress.

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Technology Short Take #49

Welcome to Technology Short Take #49 (also known as Distraction-as-a-Service)! I have here for your reading pleasure an eclectic collection of links and articles from around the web, focusing on data center-related technologies. Here’s hoping you find something useful. Bring on the content!

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Choosing CoreOS over Project Atomic

Upon hearing the news that Red Hat had released the Atomic Host variant of Red Hat Enterprise Linux, I decided that it would be a good idea for me to take a look at the CentOS flavor of the Atomic Host variant. In case you’re unfamiliar, the Atomic Host variant is the result of Project Atomic, which aimed to provide a container-optimized flavor of RHEL/CentOS/Fedora. This container-optimized flavor would leverage rpm-ostree for atomic system updates (hence the name) and come with Docker preinstalled. What I found, frankly, disappointed me.

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Running a Small Docker Swarm Cluster

In this post, I’m going to show you how to set up and run your own Docker Swarm cluster. Docker Swarm is a relatively new orchestration tool from Docker (the company) that allows you to create a cluster of hosts running Docker (the open source project) and schedule containers across the cluster. However, just scheduling and running containers across a cluster isn’t enough, so I’ll show you how to add service registration and service discovery to this environment using Consul.

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Experimenting with Docker, Registrator, and Consul

Over the last few days, I’ve been experimenting with Docker, Registrator, and Consul in an effort to explore some of the challenges involved in building a robust containerized infrastructure. While I haven’t finished fully exploring the idea (and documenting what I’ve learned), I did discover one interesting—and unexpected—interaction.

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Enabling and Mounting NFS on CoreOS

I’ve written about CoreOS a fair amount (see here, here, and here), but one of the things that is both good and bad about CoreOS is the automatic update mechanism. It’s good because you know your systems will stay up to date, but it’s bad if you haven’t taken the time to properly address how automatic updates will affect your environment (for example, you’ve manually started some Docker containers instead of using systemd unit files—when the CoreOS system reboots after an update, your Docker containers will no longer be running). Re-architecting your environment to fully account for this change in architecture and behavior is a larger discussion than can be addressed in a single blog post, but in this post I want to at least tackle one small part of the discussion: separating your persistent data. In this post, I’ll show you how to mount an NFS share on a CoreOS instance deployed on OpenStack (or any cloud that leverages cloud-init).

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Presentations in Markdown Using Deckset

Over the past couple of years, Markdown has become an important part of my computing landscape. I’ve transitioned almost all of my text-based content creation, including this blog, over to Markdown. I’d also been looking for ways that I might be able to extend my use of Markdown into creating presentations as well, but hadn’t—until recently—found a tool that fit into my workflow. Then I started using Deckset.

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Vagrant Box for Learning Open vSwitch

As you may have picked up from some of my recent posts, I’m focused on building content and tools that will help others learn new projects, products, and technologies that I think will be very relevant in the future. One such project is Open vSwitch (OVS), which I’ve written about quite a bit (you can see all OVS-related posts here). To help others work with and learn about Open vSwitch, I’ve published a new Vagrant base box.

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A Quick Thought About Mesos-DNS

A colleague recently pointed me to the recent Mesosphere announcement of Mesos-DNS, a DNS-based service discovery mechanism for Apache Mesos clusters. A comment made in the announcement got me thinking, and I wanted to briefly share my thoughts.

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