AWS Certified Solutions Architect

Quick post – I’ve been busy studying for the AWS Certified Solutions Architect – Associate exam for the past few weeks – good news, I passed it a few days ago! Shoot me a note if you ever need some solutions architected.

I primarily did this because I’ve been using AWS for years now – but so has everyone else – this would be a differentiator. There was also a lot missing in-between the cracks (I learned how to give instances in a private subnet Internet access to install/update software without giving them public IP addresses and without spending hours reading Stack Overflow posts).



Vowpal Wabbit Docker Image

Vowpal Wabbit is a really fast machine learning system.

A few months ago I put together a Docker image of Vowpal Wabbit, making it easy to run on any platform. It’s been sitting up on Github and the Docker Hub, but I forgot to write a blog post! So here it is:

You can download and run Vowpal Wabbit with one command – here is an example:

docker run --rm --volume=$(pwd):/data -t crimsonredmk/vw /data/click.train.vw -f /data/click.model.vw --loss_function logistic --link logistic --passes 1 --cache_file /data/click.cache.vw



LXC – One of My Favorite Technologies

LXC – Linux containers – are a relatively new technology available on Linux. LXC is similar to virtualization (VMWare, KVM, Parallels…), but it is much closer to the concept of BSD “jails”. There are some advantages to using LXC over virtualization:

  1. No overhead. LXC is just a container, isolating users, processes, and files, but not emulating a processor, network cards, sound, etc. The end result is no overhead in using LXC containers at all.

  2. Instant-on, instant-off, instant-setup. Starting a container takes less than a second, as does shutting down. Once you download the initial OS image (see below), setting up new containers takes seconds. No installation procedures to go through!

  3. Extremely easy to set up, use, and expand on. On Ubuntu 12.04 (and later), installation consists of one command. Setting up your first container is also 1 command. Starting that container – also 1 command. No installation, setting up users, restarting your machine, kernel modules, downloading ISOs, etc.

  4. Docker uses LXC under the hood. I haven’t used Docker much, but it’s becoming really popular.

I use LXC all the time for development work. Whenever I need a clean Ubuntu installation to run tests on (great for making sure your setup process actually works!), try things out (different databases, ideas), or installing things I know I won’t need for a long time (as soon as I’m done with school, TeXLive is going to be removed with 1 command!).

Here’s how to get started on Ubuntu 12.04 and later.

Installing LXC

sudo apt-get install lxc lxc-templates debootstrap

Setting up an Ubuntu Container

sudo lxc-create -t ubuntu -n my-first-container -- -r precise

You probably guessed – “my-first-container” is the name of the container, running Ubuntu Precise (12.04).

This command will download the latest Ubuntu 12.04 packages and install them. It will also cache the image for instant creation later (just use the same command for more containers). It will also set up simple NAT networking.

Using the Container

sudo lxc-start -n my-first-container

That’s all! You’ll be asked to log in. The Ubuntu container has a default username “ubuntu” and password “ubuntu”. Check the machine’s IP address with the command: ip addr.

Stopping the Container

sudo shutdown -h now

Maybe “halt” or “poweroff” work, but I’ve aliased this and it’s muscle-memory for me.

Deleting (Destroying) a Container

sudo lxc-destroy -n my-first-container

That’s all there is to it! The image for creation of future containers won’t be erased, but this container will be.