Home Kubernetes cluster
So I admit it – I am completely obsessed with Kubernetes. All of the web app/api deployment challenges in the past 20 years have been somewhat solved with the Kubernetes orchestration and scheduling platform. Kubernetes brings fault-tolerance, and Highly available systems if set up correctly (i.e. use a Kubernetes cloud installer). I enjoy having the power to write yaml and apply it to infrastructure and it eventually becomes what I told it to be. No longer do I need to write the scripts to do it – it does it for me 🙂
In my first kubernetes home cluster, I re-used my home router and my old media center as a single node + master, but I was hit by a 2 year old Kubernetes bug. It appears my old PC was out in the open. Since my 2 year old son likes to press power buttons, he came over and constantly pressed the power button on my Kubernetes master. This caused me to find a small mini computer that I could place in my cabinet out of view. I finally settled on this as my computer of choice. At $150/each for 4 cores, 4GB RAM, and 32GB nve, I thought it was a good deal and ample to run a few containers per node with a nfs-backed storage array.
These little machines booted via UEFI pxe (after pressing DEL for bios and selecting the Realtek boot in the save/exit page). I used this kickstart file which installed CentOS 7 minimal by passing in the ks
argument to a CentOS initramfs:
After the servers installed, I ran this script:
Note: for one of the three machines I received, I had to put modprobe br_netfilter
in /etc/rc.local
before /etc/sysctl.d/k8s.conf
would apply.