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I recently answered a question from Harsha Nalore on StackOverflow that involved using Ansible to extract the output of a command sent to a BigIP device of some sort.

As long as I’m switching site generators, it seems like a good idea to refresh the comment system as well.

I’ve switched my static site generator from Pelican to Hugo.

Update 2019-05-09 Pull request #55816 has merged, so you can now use sudo with the docker connection driver even when sudo is configured to require a password.

I often see questions from people who are attemping to perform complex text transformations in their Ansible playbooks.

A common problem for folks working with Docker is accessing resources which require authentication during the image build step.

Say you have a simple bit of code: #include <avr/io.h> #include <util/delay.h> #define LED_BUILTIN _BV(PORTB5) int main(void) { DDRB |= LED_BUILTIN; while (1) { PORTB |= LED_BUILTIN; // turn on led _delay_ms(1000); // delay 1s PORTB &= ~LED_BU…

The AVR C library, avr-libc, provide an ATOMIC_BLOCK macro that you can use to wrap critical sections of your code to ensure that interrupts are disabled while the code executes.

Pssst!

How big is an enum?

This is the third of three posts about using gdb and simavr to debug AVR code.

This is the second of three posts about using gdb and simavr to debug AVR code.

In a case of awful timing, after my recent project involving some attiny85 programming I finally got around to learning how to use simavr and gdb to help debug my AVR code.

I have a Raspberry Pi running RetroPie hooked up to a television.

The Pi Zero (and Zero W) have support for acting as a USB gadget: that means that they can be configured to act as a USB device – like a serial port, an ethernet interface, a mass storage device, etc.

Bitwarden is a password management service (like LastPass or 1Password).

Recent releases of Raspbian have adopted the use of dhcpcd to manage both dynamic and static interface configuration.

CircuitPython is “an education friendly open source derivative of MicroPython”.

The DS18B20 is a popular temperature sensor that uses the 1-Wire protocol for communication.

A question that crops up regularly on #docker is “How do I attach a container directly to my local network?”

On IRC – and other online communities – it is common to use a “pastebin” service to share snippets of code, logs, and other material, rather than pasting them directly into a conversation.

In this article, we’re going to ask Gnocchi (the OpenStack telemetry storage service) how much memory was used, on average, over the course of each day by each project in an OpenStack environment.

You can list iptables rules with rule numbers using the --line-numbers option, but this only works in list (-L) mode.

I’ve just refreshed the version of Pelican used to generate this blog, along with the associated themes and plugins.

I find myself working with Raspbian disk images fairly often.

The other day on #ansible, someone was looking for a way to safely shut down a Nova server, wait for it to stop, and then start it up again using the openstack cli.

I was recently working on a project in which I wanted to drive a simple piezo buzzer attached to a GPIO pin on a Raspberry Pi.

At $JOB we often find ourselves at customer sites where we see the same set of basic problems that we have previously encountered elsewhere (“your clocks aren’t in sync” or “your filesystem is full” or “you haven’t installed a critical update”, etc).

I use Gmail extensively for my personal email, and recently my workplace has been migrated over to Gmail as well.

I’ve been thinking about logging in the context of OpenStack and containerized service deployments.

This is now old news if you’re already following the drone industry, but if you’re not, I’d like to highlight a recent decision made by the US Court of Appeals regarding the FAA’s drone registration requirements.

It’s a bit of an embarrassment when you submit a review to Gerrit only to have it fail CI checks immediately because of something as simple as a syntax error or pep8 failure that you should have caught yourself before submitting…but you forgot to run your…

The Newton release of Heat adds support for a yaql intrinsic function, which allows you to evaluate yaql expressions in your Heat templates.

Let’s say that you have set up an environment using tripleo-quickstart and you would like to add another virtual machine to the mix that has both “external” connectivity (“external” in quotes because I am using it in the same way as the quickstart does w/…

In my last article article I introduced Gruf, a command line tool for interacting with Gerrit.

In this article I would like to introduce tripleo-quickstart, a tool that will automatically provision a virtual environment and then use TripleO to deploy an HA OpenStack on top of it.

This is a small collection of simple git tips and tricks I use to make my life easier.

(See also the followup to this article.)

I wrote earlier about systemd-nspawn, and how it can take much of the fiddly work out of setting up functional chroot environments.

systemd-nspawn has been called “chroot on steroids”, but if you think of it as Docker with a slightly different target you wouldn’t be far wrong, either.

If you have an Ansible inventory file that includes lots of per host variables, it’s not unusual for lines to get long enough that they become unwieldly, particularly if you want to discuss them in an email or write about them in some context (e.g., a blog

If you should find yourself wanting to install pyspatialite on Fedora – perhaps because you want to use the Processing plugin for QGIS – you will first need to install the following dependencies: gcc python-devel sqlite-devel geos-devel proj-devel python-…

This is the second in a loose sequence of articles looking at new features in Ansible 2.0.

When writing Ansible roles I occasionally want a way to just run a role from the command line, without having to muck about with a playbook.

This post is in response to a comment someone made on irc earlier today: [I] would really like a git lookaside cache which operated on an upstream repo, but pulled objects locally when they’re available In this post I present a proof-of-concept solution to

If you’ve tried running Ansible against a Fedora 23 system, you may have run into the following problem: fatal: [myserver]: FAILED!

As the release of Ansible 2.0 draws closer, I’d like to take a look at some of the new features that are coming down the pipe.

Someone asked on IRC about running ntpd in a container on Atomic, so I’ve put together a small example.

Many of the upgrade guides for OpenStack focus on in-place upgrades to your OpenStack environment.

In Quantum in Too Much Detail, I discussed the architecture of a Neutron deployment in detail.