Using wait conditions with Heat

Sat 30 August 2014 by Lars Kellogg-Stedman Tags openstack heat

This post accompanies my article on the Docker plugin for Heat.

In order for WaitCondition resources to operate correctly in Heat, you will need to make sure that that you have:

  • Created the necessary Heat domain and administrative user in Keystone,
  • Configured appropriate values in heat.conf for stack_user_domain, stack_domain_admin …
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nova-docker and environment variables

Thu 28 August 2014 by Lars Kellogg-Stedman Tags openstack docker

I've been playing with Docker a bit recently, and decided to take a look at the nova-docker driver for OpenStack.

The nova-docker driver lets Nova, the OpenStack Compute service, spawn Docker containers instead of hypervisor-based servers. For certain workloads, this leads to better resource utilization than you would get with …

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lvcache: a tool for managing LVM caches

Sat 16 August 2014 by Lars Kellogg-Stedman Tags lvm cache

Until recently I had a bcache based setup on my laptop, but when forced by circumstance to reinstall everything I spent some time looking for alternatives that were less disruptive to configure on an existing system.

I came across Richard Jones' article discussing the recent work to integrate dm-cache into …

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Four ways to connect a docker container to a local network

Mon 11 August 2014 by Lars Kellogg-Stedman Tags networking docker openvswitch

This article discusses four ways to make a Docker container appear on a local network. These are not suggested as practical solutions, but are meant to illustrate some of the underlying network technology available in Linux.

If you were actually going to use one of these solutions as anything other …

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gpio-watch: Run scripts in response to GPIO signals

Sat 26 July 2014 by Lars Kellogg-Stedman Tags raspberrypi gpio

For a small project I'm working on I needed to attach a few buttons to a Raspberry Pi and have some code execute in response to the button presses.

Normally I would reach for Python for a simple project like this, but constraints of the project made it necessary to implement something in C with minimal dependencies. I didn't want to write something that was tied closely to my project...

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