# Bootstrapping Kubernetes Workers In this lab you will bootstrap 3 Kubernetes worker nodes. The following virtual machines will be used: * worker0 * worker1 * worker2 ## Why Kubernetes worker nodes are responsible for running your containers. All Kubernetes clusters need one or more worker nodes. We are running the worker nodes on dedicated machines for the following reasons: * Ease of deployment and configuration * Avoid mixing arbitrary workloads with critical cluster components. We are building machine with just enough resources so we don't have to worry about wasting resources. Some people would like to run workers and cluster services anywhere in the cluster. This is totally possible, and you'll have to decide what's best for your environment. ## Provision the Kubernetes Worker Nodes Run the following commands on `worker0`, `worker1`, `worker2`: #### Move the TLS certificates in place ``` sudo mkdir -p /var/lib/kubernetes ``` ``` sudo mv ca.pem kubernetes-key.pem kubernetes.pem /var/lib/kubernetes/ ``` #### Docker Kubernetes should be compatible with the Docker 1.9.x - 1.11.x: ``` wget https://get.docker.com/builds/Linux/x86_64/docker-1.11.2.tgz ``` ``` tar -xvf docker-1.11.2.tgz ``` ``` sudo cp docker/docker* /usr/bin/ ``` Create the Docker systemd unit file: ``` sudo sh -c 'echo "[Unit] Description=Docker Application Container Engine Documentation=http://docs.docker.io [Service] ExecStart=/usr/bin/docker daemon \ --iptables=false \ --ip-masq=false \ --host=unix:///var/run/docker.sock \ --log-level=error \ --storage-driver=overlay Restart=on-failure RestartSec=5 [Install] WantedBy=multi-user.target" > /etc/systemd/system/docker.service' ``` ``` sudo systemctl daemon-reload sudo systemctl enable docker sudo systemctl start docker ``` ``` sudo docker version ``` #### kubelet The Kubernetes kubelet no longer relies on docker networking for pods! The Kubelet can now use [CNI - the Container Network Interface](https://github.com/containernetworking/cni) to manage machine level networking requirements. Download and install CNI plugins ``` sudo mkdir -p /opt/cni ``` ``` wget https://storage.googleapis.com/kubernetes-release/network-plugins/cni-c864f0e1ea73719b8f4582402b0847064f9883b0.tar.gz ``` ``` sudo tar -xvf cni-c864f0e1ea73719b8f4582402b0847064f9883b0.tar.gz -C /opt/cni ``` Download and install the Kubernetes worker binaries: ``` wget https://storage.googleapis.com/kubernetes-release/release/v1.3.6/bin/linux/amd64/kubectl wget https://storage.googleapis.com/kubernetes-release/release/v1.3.6/bin/linux/amd64/kube-proxy wget https://storage.googleapis.com/kubernetes-release/release/v1.3.6/bin/linux/amd64/kubelet ``` ``` chmod +x kubectl kube-proxy kubelet ``` ``` sudo mv kubectl kube-proxy kubelet /usr/bin/ ``` ``` sudo mkdir -p /var/lib/kubelet/ ``` ``` sudo sh -c 'echo "apiVersion: v1 kind: Config clusters: - cluster: certificate-authority: /var/lib/kubernetes/ca.pem server: https://10.240.0.20:6443 name: kubernetes contexts: - context: cluster: kubernetes user: kubelet name: kubelet current-context: kubelet users: - name: kubelet user: token: chAng3m3" > /var/lib/kubelet/kubeconfig' ``` Create the kubelet systemd unit file: ``` sudo sh -c 'echo "[Unit] Description=Kubernetes Kubelet Documentation=https://github.com/GoogleCloudPlatform/kubernetes After=docker.service Requires=docker.service [Service] ExecStart=/usr/bin/kubelet \ --allow-privileged=true \ --api-servers=https://10.240.0.20:6443,https://10.240.0.21:6443,https://10.240.0.22:6443 \ --cloud-provider= \ --cluster-dns=10.32.0.10 \ --cluster-domain=cluster.local \ --configure-cbr0=true \ --container-runtime=docker \ --docker=unix:///var/run/docker.sock \ --network-plugin=kubenet \ --kubeconfig=/var/lib/kubelet/kubeconfig \ --reconcile-cidr=true \ --serialize-image-pulls=false \ --tls-cert-file=/var/lib/kubernetes/kubernetes.pem \ --tls-private-key-file=/var/lib/kubernetes/kubernetes-key.pem \ --v=2 Restart=on-failure RestartSec=5 [Install] WantedBy=multi-user.target" > /etc/systemd/system/kubelet.service' ``` ``` sudo systemctl daemon-reload sudo systemctl enable kubelet sudo systemctl start kubelet ``` ``` sudo systemctl status kubelet --no-pager ``` #### kube-proxy ``` sudo sh -c 'echo "[Unit] Description=Kubernetes Kube Proxy Documentation=https://github.com/GoogleCloudPlatform/kubernetes [Service] ExecStart=/usr/bin/kube-proxy \ --master=https://10.240.0.20:6443 \ --kubeconfig=/var/lib/kubelet/kubeconfig \ --proxy-mode=iptables \ --v=2 Restart=on-failure RestartSec=5 [Install] WantedBy=multi-user.target" > /etc/systemd/system/kube-proxy.service' ``` ``` sudo systemctl daemon-reload sudo systemctl enable kube-proxy sudo systemctl start kube-proxy ``` ``` sudo systemctl status kube-proxy --no-pager ``` > Remember to run these steps on `worker0`, `worker1`, and `worker2`