二进制安装kubelet

1. 首先下载二进制包：https://github.com/kubernetes/kubernetes/releases
2. 解压缩 `tar -zxvf kubernetes-server-linux-amd64.tar.gz`
3. 将 `kubelet` 文件复制到 `/usr/local/bin/` 目录下：`sudo cp kubernetes/server/bin/kubelet /usr/local/bin/`
4. 创建 `kubelet` 的配置文件 `/etc/kubernetes/kubelet`，内容如下：

apiVersion: kubelet.config.k8s.io/v1beta1
kind: KubeletConfiguration
address: 0.0.0.0
port: 10250
cgroupDriver: systemd
clusterDNS:
  - 10.96.0.10
clusterDomain: cluster.local

5. 创建 `kubelet` 的 systemd unit 文件 `/etc/systemd/system/kubelet.service`，内容如下：

[Unit]
Description=kubelet: The Kubernetes Node Agent
Documentation=https://kubernetes.io/docs/

[Service]
ExecStart=/usr/local/bin/kubelet \
  --config=/etc/kubernetes/kubelet \
  --kubeconfig=/etc/kubernetes/kubelet.kubeconfig \
  --bootstrap-kubeconfig=/etc/kubernetes/bootstrap.kubeconfig \
  --cert-dir=/etc/kubernetes/pki \
  --pod-manifest-path=/etc/kubernetes/manifests \
  --cgroup-driver=systemd \
  --rotate-certificates \
  --allow-privileged=true \
  --fail-swap-on=false \
  --runtime-cgroups=/systemd/system.slice \
  --kubelet-cgroups=/systemd/system.slice \
  --feature-gates=RotateKubeletServerCertificate=true \
  --feature-gates=RotateKubeletClientCertificate=true \
  --eviction-hard=memory.available<300Mi,nodefs.available<10%,nodefs.inodesFree<5%,imagefs.available<10%,imagefs.inodesFree<5% \
  --eviction-soft=memory.available<500Mi,nodefs.available<20%,nodefs.inodesFree<10%,imagefs.available<20%,imagefs.inodesFree<10%
Restart=always
StartLimitInterval=0
RestartSec=10

[Install]
WantedBy=multi-user.target

6. 启动 `kubelet`：`sudo systemctl enable kubelet && sudo systemctl start kubelet`
7. 检查 `kubelet` 是否正常工作：`sudo systemctl status kubelet`