Hardware and Cost
This site is sharing how my steps to setup a K3S cluster and run pods ( docker containers ) into low cost hardwares such as Raspberry Pi with another alternative for generating sweet money and build up home gateway ( HomeBridge ) to connect my existing iot devices ( Android Smart TV, infra red light and fan… ) those are not support Apple HomeKit officially. Total cost just around $120 without the part of MySQL server.
- 1 x Raspberry Pi4 ( https://www.raspberrypi.com )
- 2 x OrangePi LTS4 – More cost effective hardware rather then Raspberry PI that I found. ( http://www.orangepi.org )
- 6ports USB charger, USB type B to type C cables for whole Pi power
- Pi cluster case with fan
- 3 x Sandisk 32GB microSD card
- My old Synology NAS which model support docker – This is my existing storage installed docker version of mariadb for k3s cluster database and failover feature. Reason I choose external database instead of etcd. Normally etcd is good but not for “Pi, the disk IO speed is too slow if etcd database running on microSD card. I tried couple times need to reinstall k3s in a month due to etcd corruption.
K3S vs stand alone mini PC with Docker

- Containers auto failover when K3S node hardware/software issue. Stand alone PC doesn’t take this advantage.
- Repair cost of of K3S “Pi” cluster is much reasonable . Just replace each small part if hardware failured rather than all in one PC.
- Closer to 7 x 24 environment using “Pi” cluster. But Mini PC has single point of failure problem and more maintenance effort when happened.