# monok8s
An Alpine-based Kubernetes cluster image for Mono's Gateway Development Kit

https://docs.mono.si/gateway-development-kit/getting-started

## Features
 * A/B deployment
 * Read-only RootFS
 * k8s style OS upgrade (see Upgrading)

## DISCLAIMER

 * This is not your everyday linux image! It is best suited for users that is already familiar
   with k8s. For first-timers, you may want to try the default config that gives you a ready-to-use
   cluster and get yourself started from there

 * USE AT YOUR OWN RISKS. I leverage ChatGPT heavily for this.

## Table of Contents
1. Flashing
   - [USB](docs/flashing-usb.md)
   - [Over network (tftp)](docs/flashing-network.md)
2. [Upgrading](docs/ota.md)
3. Getting shell access to the host
   - UART. The thing you did in first time flashing.
   - [Install an ssh pod](docs/installing-ssh-pod.md) (Recommended)

## Build

Prerequisites
* make
* Docker
* curl (downloading dependency packages, kubelet, crio, etc)
* go (building clitools, control-agent)
   * controller-gen (see [clitools readme](clitools/README.md))
* git (cloning uboot repo because uboot does not provide direct downloads)

```
make release
```

The default configuration will boot as a first time control-plane.

For control-plane
```
make cluster-config \
  MKS_HOSTNAME=monok8s-master \
  MKS_CLUSTER_ROLE=control-plane \
  MKS_INIT_CONTROL_PLANE=true \
  MKS_MGMT_ADDRESS=10.0.0.10/24 \
  MKS_APISERVER_ADVERTISE_ADDRESS=10.0.0.10
```

For worker
```
make cluster-config \
  MKS_HOSTNAME=monok8s-worker \
  MKS_CLUSTER_ROLE=worker \
  MKS_INIT_CONTROL_PLANE=no \
  MKS_MGMT_ADDRESS=10.0.0.10/24 \
  MKS_APISERVER_ADVERTISE_ADDRESS=10.0.0.10 \
  MKS_API_SERVER_ENDPOINT=10.0.0.1:6443 \
  MKS_CNI_PLUGIN=none \
  MKS_BOOTSTRAP_TOKEN=abcd12.ef3456789abcdef0 \
  MKS_DISCOVERY_TOKEN_CA_CERT_HASH=sha256:9f1c2b3a4d5e6f7890abc1234567890abcdef1234567890abcdef1234567890ab
```

Check inside [configs/cluster.env.default](configs/cluster.env.default) for configuration details

### Making sub stages
```bash
make build-base # The image that builds the kernel and everything
make kernel     # Builds our kernel from NXP
make initramfs
make itb        # Builds out/board.itb (contains the kernel and the initramfs)
```