March 21, 2020

Introducing stormlight-iso

I decided in December that I want to start coding again. I've been in engineering leadership roles for the past two and a half years, which has kept me away from coding. I miss being in a flow state working on low-level technical problems for hours on end. One of the areas I'm missing out on is mastering kubernetes. I use kubernetes at work, but I removed enough that it's difficult to grok the details.

Therefore, last winter, I bought three Intel NUCs (8i3BEK1) to be the basis of my kubernetes homelab. After physically building each machine, connecting them to my network, and manually installing Ubuntu 18.04 three times, I decided that I didn't want to do this again. I am, to my wife's annoyance, forgetful. I have difficulty remembering to buy milk when going to the grocery store with the sole intention of buying milk. Imagine what the three NUCs looked like after I installed Ubuntu three times. Not very similar.

Luckily, Ubuntu had an installation method called preseeding to install itself with pre-configured answers to the dialogue prompts. Essentially, this allowed me to remaster the installation ISO so that I did not have to manually enter resposes to dialog prompts. After following the instructions from the wiki, I created an ISO that installed Ubuntu Server from start to finish without any keyboard prompts. With the ISO, I installed Ubuntu identically on my three NUCs and went about my business installing Kubernetes.

This development took several weeks because I became a father at the same time. And apparently, newborns need to feed every few hours. Though, I admit that's a coverup to the real reason it took so long. I didn't know how to do this. I've never dealt with the debian installer (what Ubuntu uses for installation), manipulating initrd, or configuring VirtualBox images to mimic intel NUCs for development. And then to top it all off, I still had to deal with differences in linux and mac tools.

Nevertheless, I codified my work into the stormlight-iso project on GitHub (stormlight is the name of my kubernetes cluster). Now I can forget the entire process without guilt. And if you'd like, you too can forget how to do it too!

With that, I'll leave you at the beginning of the README.

stormlight-iso

This project builds an Ubuntu 18.04 ISO to install Ubuntu unattended (no keyboard interaction) on Intel NUC 8 Core i3 machines.

This project assumes:

  • Installation of Ubuntu via USB stick
  • ISO built on a Mac OSX machine
  • Intel NUC has a static IP assigned to it to SSH to the machine (or some way for you to find the IP of your machine after Ubuntu has been installed and booted)
  • A USB stick with minimum 100MB of space

The project is designed to minimize the amount of physical effort to set up an Intel NUC because the author is lazy and forgetful. Also, the author has several Intel NUCs and manually entering in configuration value is error prone. Here's what the installation process looks like.

  1. Build the stormlight.iso with preseed config and an ssh public key
  2. Create a bootable USB from the stormlight.iso
  3. Walk over to the Intel NUC, plug in USB stick, and power on the machine
  4. Wait until the machine powers itself down after the installation (roughly 10-15 mins). "Look ma, no keyboard!"
  5. Unplug USB stick and power on the machine.
  6. Walk back to your computer and SSH into the machine.

That's it!