k3s running in Raspberry Pi 4b 8G

Preparing the OS

Get the Pi OS 64 bits on this url

After create the Micro SD card, mount the card and add the text cgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory at the end of the first line in the file cmdline.txt (make sure its only single line in the file)

Installing the Docker

sudo apt-get update && sudo apt-get upgrade
curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh
sudo usermod -aG docker pi

docker version
docker info

docker run hello-world

Installing the k3s

curl -sfL https://get.k3s.io | INSTALL_K3S_CHANNEL=latest sh -
sudo chmod 644 /etc/rancher/k3s/k3s.yaml
echo "K3S_KUBECONFIG_MODE=\"644\"" >> /etc/systemd/system/k3s.service.env

Installing and configuring the java environment

• jdk

sudo apt update
sudo apt install default-jdk
java –version

• maven

sudo mkdir /opt/tools
sudo chown pi:pi /opt/tools
wget https://downloads.apache.org/maven/maven-3/3.6.3/binaries/apache-maven-3.6.3-bin.tar.gz
tar -xzvf apache-maven-3.6.3-bin.tar.gz
mv apache-maven-3.6.3 /opt/tools

Edit the profile

vi ~/.profile

and in the end of file add the lines below

M2_HOME=/opt/tools/apache-maven-3.6.3
PATH=$PATH:$M2_HOME/bin

Building and Running

• building:

mvn clean package -f api-zipcode
mvn docker:build -f api-zipcode/api-zipcode-infraestructure

• running:

docker run -it --rm --name api -p 1401:1401 api-zipcode:1.0.0

• testing

curl http://<raspberry server>:1401/zipcode/37188

Deploying in kubernetes

• pushing the image to the registry

mvn -Ddocker.registry=localhost:5000 -Ddocker.username=admin -Ddocker.password=admin \
    docker:push -f api-zipcode/api-zipcode-infraestructure

mvn docker:remove -f api-zipcode/api-zipcode-infraestructure    

• listing the tags inside the registry

curl -u admin:admin http://<raspberry server>:5000/v2/api-zipcode/tags/list

• configuring the linux host

sudo nano /etc/hosts

in the end of file add the lines below

127.0.0.1       registry.localhost

• adding the registry configuration on k3s

sudo vim /etc/rancher/k3s/registries.yaml

Add the lines below

mirrors:
  "registry.localhost:5000":
    endpoint:
      - "http://registry.localhost:5000"
configs:
  "registry.localhost:5000":
    auth:
      username: admin # this is the registry username
      password: admin # this is the registry password

• deploying the service

kubectl apply -f kubernetes/deploy.yaml

• testing

curl http://<raspberry server>/zipcode/37188