Moving to GitHub

Wed 13 November 2013 by Lars Kellogg-Stedman Tags blog

This blog has been hosted on scriptogram for the past year or so. Unfortunately, while I like the publish-via-Dropbox mechanism, there have been enough problems recently that I've finally switched over to using GitHub Pages for hosting. I've been thinking about doing this for a while, but the things that finally pushed me to make the change were:

  • Sync problems that would prevent new posts from appearing (and that at least once caused posts to disappear).
  • Lack of any response to bug reports by the site maintainers.

A benefit of the publish-via-Dropbox mechanism is, of course, that I already had all the data and didn't need to go through any sort of export process.

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A random collection of OpenStack Tools

Tue 12 November 2013 by Lars Kellogg-Stedman Tags openstack

I've been working with OpenStack a lot recently, and I've ended up with a small collection of utilities that make my life easier. On the odd chance that they'll make your life easier, too, I thought I'd hilight them here.

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Why does the Neutron documentation recommend three interfaces?

Mon 28 October 2013 by Lars Kellogg-Stedman Tags openstack neutron networking

The documentation for configuring Neutron recommends that a network controller has three physical interfaces:

Before you start, set up a machine to be a dedicated network node. Dedicated network nodes should have the following NICs: the management NIC (called MGMT_INTERFACE), the data NIC (called DATA_INTERFACE), and the external NIC (called EXTERNAL_INTERFACE).

People occasionally ask, "why three interfaces? What if I only have two?", so I wanted to provide an extended answer that might help people understand what the interfaces are for and what trade-offs are involved in using fewer interfaces.

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Automatic hostname entries for libvirt domains

Fri 04 October 2013 by Lars Kellogg-Stedman Tags libvirt virtualization

Have you ever wished that you could use libvirt domain names as hostnames? So that you could do something like this:

$ virt-install -n anewhost ...
$ ssh clouduser@anewhost

Since this is something that would certainly make my life convenient, I put together a small script called virt-hosts that makes this possible …

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Interrupts on the PiFace

Mon 05 August 2013 by Lars Kellogg-Stedman Tags raspberrypi python piface

I recently acquired both a Raspberry Pi and a PiFace IO board. I had a rough time finding examples of how to read the input ports via interrupts (rather than periodically polling for values), especially for the newer versions of the PiFace python libraries.

After a little research, here's some …

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