2017-08-29 00:19:25 +03:00
# Bootstrapping the Kubernetes Worker Nodes
In this lab you will bootstrap three Kubernetes worker nodes. The following components will be installed on each node: [runc ](https://github.com/opencontainers/runc ), [container networking plugins ](https://github.com/containernetworking/cni ), [cri-o ](https://github.com/kubernetes-incubator/cri-o ), [kubelet ](https://kubernetes.io/docs/admin/kubelet ), and [kube-proxy ](https://kubernetes.io/docs/concepts/cluster-administration/proxies ).
## Prerequisites
The commands in this lab must be run on each worker instance: `worker-0` , `worker-1` , and `worker-2` . Login to each worker instance using the `gcloud` command. Example:
```
gcloud compute ssh worker-0
```
## Provisioning a Kubernetes Worker Node
### Install the cri-o OS Dependencies
Add the `alexlarsson/flatpak` [PPA ](https://launchpad.net/ubuntu/+ppas ) which hosts the `libostree` package:
```
sudo add-apt-repository -y ppa:alexlarsson/flatpak
```
```
sudo apt-get update
```
Install the OS dependencies required by the cri-o container runtime:
```
sudo apt-get install -y socat libgpgme11 libostree-1-1
```
### Download and Install Worker Binaries
```
wget -q --show-progress --https-only --timestamping \
https://github.com/containernetworking/plugins/releases/download/v0.6.0/cni-plugins-amd64-v0.6.0.tgz \
https://github.com/opencontainers/runc/releases/download/v1.0.0-rc4/runc.amd64 \
https://storage.googleapis.com/kubernetes-the-hard-way/crio-amd64-v1.0.0-beta.0.tar.gz \
https://storage.googleapis.com/kubernetes-release/release/v1.7.4/bin/linux/amd64/kubectl \
https://storage.googleapis.com/kubernetes-release/release/v1.7.4/bin/linux/amd64/kube-proxy \
https://storage.googleapis.com/kubernetes-release/release/v1.7.4/bin/linux/amd64/kubelet
```
Create the installation directories:
```
sudo mkdir -p \
/etc/containers \
/etc/cni/net.d \
/etc/crio \
/opt/cni/bin \
/usr/local/libexec/crio \
/var/lib/kubelet \
/var/lib/kube-proxy \
/var/lib/kubernetes \
/var/run/kubernetes
```
Install the worker binaries:
```
sudo tar -xvf cni-plugins-amd64-v0.6.0.tgz -C /opt/cni/bin/
```
```
tar -xvf crio-amd64-v1.0.0-beta.0.tar.gz
```
```
chmod +x kubectl kube-proxy kubelet runc.amd64
```
```
sudo mv runc.amd64 /usr/local/bin/runc
```
```
sudo mv crio crioctl kpod kubectl kube-proxy kubelet /usr/local/bin/
```
```
sudo mv conmon pause /usr/local/libexec/crio/
```
### Configure CNI Networking
Retrieve the Pod CIDR range for the current compute instance:
```
POD_CIDR=$(curl -s -H "Metadata-Flavor: Google" \
http://metadata.google.internal/computeMetadata/v1/instance/attributes/pod-cidr)
```
Create the `bridge` network configuration file:
```
cat > 10-bridge.conf < < EOF
{
"cniVersion": "0.3.1",
"name": "bridge",
"type": "bridge",
"bridge": "cnio0",
"isGateway": true,
"ipMasq": true,
"ipam": {
"type": "host-local",
"ranges": [
[{"subnet": "${POD_CIDR}"}]
],
"routes": [{"dst": "0.0.0.0/0"}]
}
}
EOF
```
Create the `loopback` network configuration file:
```
cat > 99-loopback.conf < < EOF
{
"cniVersion": "0.3.1",
"type": "loopback"
}
EOF
```
Move the network configuration files to the CNI configuration directory:
```
sudo mv 10-bridge.conf 99-loopback.conf /etc/cni/net.d/
```
### Configure the CRI-O Container Runtime
```
sudo mv crio.conf seccomp.json /etc/crio/
```
```
sudo mv policy.json /etc/containers/
```
```
cat > crio.service < < EOF
[Unit]
Description=CRI-O daemon
Documentation=https://github.com/kubernetes-incubator/cri-o
[Service]
ExecStart=/usr/local/bin/crio
Restart=always
RestartSec=10s
[Install]
WantedBy=multi-user.target
EOF
```
### Configure the Kubelet
```
sudo mv ${HOSTNAME}-key.pem ${HOSTNAME}.pem /var/lib/kubelet/
```
```
sudo mv ${HOSTNAME}.kubeconfig /var/lib/kubelet/kubeconfig
```
```
sudo mv ca.pem /var/lib/kubernetes/
```
Create the `kubelet.service` systemd unit file:
```
cat > kubelet.service < < EOF
[Unit]
Description=Kubernetes Kubelet
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=crio.service
Requires=crio.service
[Service]
ExecStart=/usr/local/bin/kubelet \\
2017-09-02 06:45:42 +03:00
--authorization-mode=Webhook \\
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--allow-privileged=true \\
--cluster-dns=10.32.0.10 \\
--cluster-domain=cluster.local \\
--container-runtime=remote \\
--container-runtime-endpoint=unix:///var/run/crio.sock \\
--enable-custom-metrics \\
--image-pull-progress-deadline=2m \\
--image-service-endpoint=unix:///var/run/crio.sock \\
--kubeconfig=/var/lib/kubelet/kubeconfig \\
--network-plugin=cni \\
--pod-cidr=${POD_CIDR} \\
--register-node=true \\
--require-kubeconfig \\
--runtime-request-timeout=10m \\
--tls-cert-file=/var/lib/kubelet/${HOSTNAME}.pem \\
--tls-private-key-file=/var/lib/kubelet/${HOSTNAME}-key.pem \\
--v=2
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
EOF
```
### Configure the Kubernetes Proxy
```
sudo mv kube-proxy.kubeconfig /var/lib/kube-proxy/kubeconfig
```
Create the `kube-proxy.service` systemd unit file:
```
cat > kube-proxy.service < < EOF
[Unit]
Description=Kubernetes Kube Proxy
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
[Service]
ExecStart=/usr/local/bin/kube-proxy \\
--cluster-cidr=10.200.0.0/16 \\
--kubeconfig=/var/lib/kube-proxy/kubeconfig \\
--proxy-mode=iptables \\
--v=2
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
EOF
```
### Start the Worker Services
```
sudo mv crio.service kubelet.service kube-proxy.service /etc/systemd/system/
```
```
sudo systemctl daemon-reload
```
```
sudo systemctl enable crio kubelet kube-proxy
```
```
sudo systemctl start crio kubelet kube-proxy
```
> Remember to run the above commands on each worker node: `worker-0`, `worker-1`, and `worker-2`.
## Verification
Login to one of the controller nodes:
```
gcloud compute ssh controller-0
```
List the registered Kubernetes nodes:
```
kubectl get nodes
```
> output
```
NAME STATUS AGE VERSION
worker-0 Ready 5m v1.7.4
worker-1 Ready 3m v1.7.4
worker-2 Ready 7s v1.7.4
```
Next: [Configuring kubectl for Remote Access ](10-configuring-kubectl.md )
