部署 Kubernetes Workers 节点

本部分将会部署三个 Kubernetes Worker 节点。每个节点上将会安装以下服务：runc, gVisor, container networking plugins, containerd, kubelet, 和 kube-proxy。

事前准备

以下命令需要在所有 worker 节点上面都运行一遍，包括 worker-0, worker-1 和 worker-2。可以使用 gcloud 命令登录到 worker 节点上，比如

gcloud compute ssh worker-0

可以使用 tmux 同时登录到三个 Worker 节点上，加快部署步骤。

部署 Kubernetes Worker 节点

安装 OS 依赖组件：

sudo apt-get update
sudo apt-get -y install socat conntrack ipset

socat 命令用于支持 kubectl port-forward 命令。

下载并安装 worker 二进制文件

wget -q --show-progress --https-only --timestamping \
  https://github.com/kubernetes-sigs/cri-tools/releases/download/v1.12.0/crictl-v1.12.0-linux-amd64.tar.gz \
  https://storage.googleapis.com/kubernetes-the-hard-way/runsc-50c283b9f56bb7200938d9e207355f05f79f0d17 \
  https://github.com/opencontainers/runc/releases/download/v1.0.0-rc5/runc.amd64 \
  https://github.com/containernetworking/plugins/releases/download/v0.6.0/cni-plugins-amd64-v0.6.0.tgz \
  https://github.com/containerd/containerd/releases/download/v1.2.0-rc.0/containerd-1.2.0-rc.0.linux-amd64.tar.gz \
  https://storage.googleapis.com/kubernetes-release/release/v1.12.0/bin/linux/amd64/kubectl \
  https://storage.googleapis.com/kubernetes-release/release/v1.12.0/bin/linux/amd64/kube-proxy \
  https://storage.googleapis.com/kubernetes-release/release/v1.12.0/bin/linux/amd64/kubelet

创建安装目录：

sudo mkdir -p \
  /etc/cni/net.d \
  /opt/cni/bin \
  /var/lib/kubelet \
  /var/lib/kube-proxy \
  /var/lib/kubernetes \
  /var/run/kubernetes

安装 worker 二进制文件

sudo mv runsc-50c283b9f56bb7200938d9e207355f05f79f0d17 runsc
sudo mv runc.amd64 runc
chmod +x kubectl kube-proxy kubelet runc runsc
sudo mv kubectl kube-proxy kubelet runc runsc /usr/local/bin/
sudo tar -xvf crictl-v1.12.0-linux-amd64.tar.gz -C /usr/local/bin/
sudo tar -xvf cni-plugins-amd64-v0.6.0.tgz -C /opt/cni/bin/
sudo tar -xvf containerd-1.2.0-rc.0.linux-amd64.tar.gz -C /

配置 CNI 网路

查询当前计算节点的 Pod CIDR 范围：

POD_CIDR=$(curl -s -H "Metadata-Flavor: Google" \
  http://metadata.google.internal/computeMetadata/v1/instance/attributes/pod-cidr)

生成 bridge 网络插件配置文件

cat <<EOF | sudo tee /etc/cni/net.d/10-bridge.conf
{
    "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

生成 loopback 网络插件配置文件

cat <<EOF | sudo tee /etc/cni/net.d/99-loopback.conf
{
    "cniVersion": "0.3.1",
    "type": "loopback"
}
EOF

配置 containerd

sudo mkdir -p /etc/containerd/

# Untrusted workloads will be run using the gVisor (runsc) runtime.
cat << EOF | sudo tee /etc/containerd/config.toml
[plugins]
  [plugins.cri.containerd]
    snapshotter = "overlayfs"
    [plugins.cri.containerd.default_runtime]
      runtime_type = "io.containerd.runtime.v1.linux"
      runtime_engine = "/usr/local/bin/runc"
      runtime_root = ""
    [plugins.cri.containerd.untrusted_workload_runtime]
      runtime_type = "io.containerd.runtime.v1.linux"
      runtime_engine = "/usr/local/bin/runsc"
      runtime_root = "/run/containerd/runsc"
    [plugins.cri.containerd.gvisor]
      runtime_type = "io.containerd.runtime.v1.linux"
      runtime_engine = "/usr/local/bin/runsc"
      runtime_root = "/run/containerd/runsc"
EOF

# Create the containerd.service systemd unit file
cat <<EOF | sudo tee /etc/systemd/system/containerd.service
[Unit]
Description=containerd container runtime
Documentation=https://containerd.io
After=network.target

[Service]
ExecStartPre=/sbin/modprobe overlay
ExecStart=/bin/containerd
Restart=always
RestartSec=5
Delegate=yes
KillMode=process
OOMScoreAdjust=-999
LimitNOFILE=1048576
LimitNPROC=infinity
LimitCORE=infinity

[Install]
WantedBy=multi-user.target
EOF

配置 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/

生成 kubelet.service systemd 配置文件：

# The resolvConf configuration is used to avoid loops
# when using CoreDNS for service discovery on systems running systemd-resolved.
cat <<EOF | sudo tee /var/lib/kubelet/kubelet-config.yaml
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
authentication:
  anonymous:
    enabled: false
  webhook:
    enabled: true
  x509:
    clientCAFile: "/var/lib/kubernetes/ca.pem"
authorization:
  mode: Webhook
clusterDomain: "cluster.local"
clusterDNS:
  - "10.32.0.10"
podCIDR: "${POD_CIDR}"
resolvConf: "/run/systemd/resolve/resolv.conf"
runtimeRequestTimeout: "15m"
tlsCertFile: "/var/lib/kubelet/${HOSTNAME}.pem"
tlsPrivateKeyFile: "/var/lib/kubelet/${HOSTNAME}-key.pem"
EOF

cat <<EOF | sudo tee /etc/systemd/system/kubelet.service
[Unit]
Description=Kubernetes Kubelet
Documentation=https://github.com/kubernetes/kubernetes
After=containerd.service
Requires=containerd.service

[Service]
ExecStart=/usr/local/bin/kubelet \\
  --config=/var/lib/kubelet/kubelet-config.yaml \\
  --container-runtime=remote \\
  --container-runtime-endpoint=unix:///var/run/containerd/containerd.sock \\
  --image-pull-progress-deadline=2m \\
  --kubeconfig=/var/lib/kubelet/kubeconfig \\
  --network-plugin=cni \\
  --register-node=true \\
  --v=2
Restart=on-failure
RestartSec=5

[Install]
WantedBy=multi-user.target
EOF

配置 Kube-Proxy

sudo mv kube-proxy.kubeconfig /var/lib/kube-proxy/kubeconfig

生成 kube-proxy.service systemd 配置文件：

cat <<EOF | sudo tee /var/lib/kube-proxy/kube-proxy-config.yaml
kind: KubeProxyConfiguration
apiVersion: kubeproxy.config.k8s.io/v1alpha1
clientConnection:
  kubeconfig: "/var/lib/kube-proxy/kubeconfig"
mode: "iptables"
clusterCIDR: "10.200.0.0/16"
EOF

cat <<EOF | sudo tee /etc/systemd/system/kube-proxy.service
[Unit]
Description=Kubernetes Kube Proxy
Documentation=https://github.com/kubernetes/kubernetes

[Service]
ExecStart=/usr/local/bin/kube-proxy \\
  --config=/var/lib/kube-proxy/kube-proxy-config.yaml
Restart=on-failure
RestartSec=5

[Install]
WantedBy=multi-user.target
EOF

启动 worker 服务

sudo systemctl daemon-reload
sudo systemctl enable containerd kubelet kube-proxy
sudo systemctl start containerd kubelet kube-proxy

记得在所有 worker 节点上面都运行一遍，包括 worker-0, worker-1 和 worker-2。

验证

登入任意一台控制节点查询 Nodes 列表

gcloud compute ssh controller-0 \
  --command "kubectl get nodes --kubeconfig admin.kubeconfig"

输出为

NAME       STATUS   ROLES    AGE   VERSION
worker-0   Ready    <none>   35s   v1.12.0
worker-1   Ready    <none>   36s   v1.12.0
worker-2   Ready    <none>   36s   v1.12.0

下一步：配置 Kubectl。