自动化Linux上Kubernetes(K8S)安装的脚本方案

方案概述

以下是一个完整的自动化脚本方案，用于在Linux系统上安装Kubernetes集群。这个脚本支持主节点和工作节点的安装配置。

完整安装脚本

#!/bin/bash

# Kubernetes自动化安装脚本
# 支持Ubuntu/CentOS系统
# 使用方式: sudo ./install_k8s.sh [master|worker] [options]

set -e

# 参数定义
ROLE=""
K8S_VERSION="1.28.0"
POD_NETWORK_CIDR="10.244.0.0/16"
SERVICE_CIDR="10.96.0.0/12"
MASTER_IP=""
TOKEN=""
TOKEN_HASH=""
INSTALL_DASHBOARD=false
INSTALL_METRICS=false
INSTALL_ISTIO=false
CONTAINER_RUNTIME="containerd"

# 颜色定义
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
NC='\033[0m' # No Color

# 显示帮助信息
usage() {
    echo "Usage: $0 [master|worker] [options]"
    echo "Options:"
    echo "  --k8s-version <version>      Kubernetes版本 (默认: $K8S_VERSION)"
    echo "  --pod-network-cidr <cidr>   Pod网络CIDR (默认: $POD_NETWORK_CIDR)"
    echo "  --service-cidr <cidr>       服务CIDR (默认: $SERVICE_CIDR)"
    echo "  --master-ip <ip>            主节点IP (工作节点需要)"
    echo "  --token <token>             加入集群的token (工作节点需要)"
    echo "  --token-hash <hash>         加入集群的token hash (工作节点需要)"
    echo "  --container-runtime <runtime> 容器运行时 (containerd/docker, 默认: $CONTAINER_RUNTIME)"
    echo "  --install-dashboard         安装Kubernetes Dashboard"
    echo "  --install-metrics           安装Metrics Server"
    echo "  --install-istio             安装Istio服务网格"
    exit 1
}

# 检查命令是否存在
command_exists() {
    command -v "$@" >/dev/null 2>&1
}

# 检查是否为root用户
check_root() {
    if [ "$(id -u)" -ne 0 ]; then
        echo -e "${RED}错误: 必须使用root用户运行此脚本${NC}" >&2
        exit 1
    fi
}

# 检测操作系统
detect_os() {
    if [ -f /etc/os-release ]; then
        . /etc/os-release
        OS=$ID
        VERSION=$VERSION_ID
    elif command_exists lsb_release; then
        OS=$(lsb_release -si | tr '[:upper:]' '[:lower:]')
        VERSION=$(lsb_release -sr)
    else
        OS=$(uname -s | tr '[:upper:]' '[:lower:]')
        VERSION=$(uname -r)
    fi
}

# 安装必要工具
install_tools() {
    echo -e "${GREEN}[INFO] 安装必要工具...${NC}"

    if [ "$OS" = "ubuntu" ] || [ "$OS" = "debian" ]; then
        apt-get update
        apt-get install -y apt-transport-https ca-certificates curl gnupg lsb-release software-properties-common
    elif [ "$OS" = "centos" ] || [ "$OS" = "rhel" ] || [ "$OS" = "amzn" ]; then
        yum install -y yum-utils device-mapper-persistent-data lvm2
    else
        echo -e "${RED}错误: 不支持的操作系统${NC}"
        exit 1
    fi
}

# 禁用交换空间
disable_swap() {
    echo -e "${GREEN}[INFO] 禁用交换空间...${NC}"
    swapoff -a
    sed -i '/swap/s/^\(.*\)$/#\1/g' /etc/fstab
}

# 配置内核参数
configure_kernel() {
    echo -e "${GREEN}[INFO] 配置内核参数...${NC}"

    cat <<EOF | tee /etc/modules-load.d/k8s.conf
overlay
br_netfilter
EOF

    modprobe overlay
    modprobe br_netfilter

    cat <<EOF | tee /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-iptables  = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.ipv4.ip_forward                 = 1
EOF

    sysctl --system
}

# 安装容器运行时
install_container_runtime() {
    echo -e "${GREEN}[INFO] 安装容器运行时: $CONTAINER_RUNTIME...${NC}"

    if [ "$CONTAINER_RUNTIME" = "containerd" ]; then
        install_containerd
    elif [ "$CONTAINER_RUNTIME" = "docker" ]; then
        install_docker
    else
        echo -e "${RED}错误: 不支持的容器运行时: $CONTAINER_RUNTIME${NC}"
        exit 1
    fi
}

# 安装containerd
install_containerd() {
    if command_exists containerd; then
        echo -e "${YELLOW}[INFO] containerd 已安装，跳过安装${NC}"
        return
    fi

    if [ "$OS" = "ubuntu" ] || [ "$OS" = "debian" ]; then
        curl -fsSL https://download.docker.com/linux/$OS/gpg | gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
        echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/$OS $(lsb_release -cs) stable" | tee /etc/apt/sources.list.d/docker.list >/dev/null
        apt-get update
        apt-get install -y containerd.io
    elif [ "$OS" = "centos" ] || [ "$OS" = "rhel" ] || [ "$OS" = "amzn" ]; then
        yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
        yum install -y containerd.io
    fi

    mkdir -p /etc/containerd
    containerd config default | tee /etc/containerd/config.toml >/dev/null
    sed -i 's/SystemdCgroup = false/SystemdCgroup = true/g' /etc/containerd/config.toml
    systemctl restart containerd
    systemctl enable containerd
}

# 安装docker
install_docker() {
    if command_exists docker; then
        echo -e "${YELLOW}[INFO] Docker 已安装，跳过安装${NC}"
        return
    fi

    if [ "$OS" = "ubuntu" ] || [ "$OS" = "debian" ]; then
        curl -fsSL https://download.docker.com/linux/$OS/gpg | gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
        echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/$OS $(lsb_release -cs) stable" | tee /etc/apt/sources.list.d/docker.list >/dev/null
        apt-get update
        apt-get install -y docker-ce docker-ce-cli containerd.io
    elif [ "$OS" = "centos" ] || [ "$OS" = "rhel" ] || [ "$OS" = "amzn" ]; then
        yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
        yum install -y docker-ce docker-ce-cli containerd.io
    fi

    mkdir -p /etc/docker
    cat <<EOF | tee /etc/docker/daemon.json
{
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "storage-driver": "overlay2"
}
EOF

    systemctl restart docker
    systemctl enable docker
}

# 安装kubeadm, kubelet和kubectl
install_kube_packages() {
    echo -e "${GREEN}[INFO] 安装kubeadm, kubelet和kubectl...${NC}"

    if [ "$OS" = "ubuntu" ] || [ "$OS" = "debian" ]; then
        curl -fsSL https://packages.cloud.google.com/apt/doc/apt-key.gpg | gpg --dearmor -o /etc/apt/keyrings/kubernetes-archive-keyring.gpg
        echo "deb [signed-by=/etc/apt/keyrings/kubernetes-archive-keyring.gpg] https://apt.kubernetes.io/ kubernetes-xenial main" | tee /etc/apt/sources.list.d/kubernetes.list
        apt-get update
        apt-get install -y kubelet=$K8S_VERSION-00 kubeadm=$K8S_VERSION-00 kubectl=$K8S_VERSION-00
        apt-mark hold kubelet kubeadm kubectl
    elif [ "$OS" = "centos" ] || [ "$OS" = "rhel" ] || [ "$OS" = "amzn" ]; then
        cat <<EOF | tee /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
EOF
        yum install -y kubelet-$K8S_VERSION kubeadm-$K8S_VERSION kubectl-$K8S_VERSION
        yum versionlock add kubelet kubeadm kubectl
    fi

    systemctl enable kubelet
}

# 初始化主节点
init_master() {
    echo -e "${GREEN}[INFO] 初始化Kubernetes主节点...${NC}"

    kubeadm init \
        --apiserver-advertise-address=$(hostname -I | awk '{print $1}') \
        --pod-network-cidr=$POD_NETWORK_CIDR \
        --service-cidr=$SERVICE_CIDR \
        --kubernetes-version=$K8S_VERSION

    # 配置kubectl
    mkdir -p $HOME/.kube
    cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
    chown $(id -u):$(id -g) $HOME/.kube/config

    # 获取加入集群的token和hash
    TOKEN=$(kubeadm token create)
    TOKEN_HASH=$(openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //')

    echo -e "${GREEN}[INFO] 主节点初始化完成!${NC}"
    echo -e "${YELLOW}工作节点加入集群命令:${NC}"
    echo "kubeadm join $(hostname -I | awk '{print $1}'):6443 --token $TOKEN --discovery-token-ca-cert-hash sha256:$TOKEN_HASH"
}

# 安装网络插件 (Flannel)
install_network_plugin() {
    echo -e "${GREEN}[INFO] 安装Flannel网络插件...${NC}"
    kubectl apply -f https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml
}

# 安装Dashboard
install_dashboard() {
    echo -e "${GREEN}[INFO] 安装Kubernetes Dashboard...${NC}"

    kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.7.0/aio/deploy/recommended.yaml

    # 创建管理员用户
    cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kubernetes-dashboard
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: admin-user
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: admin-user
  namespace: kubernetes-dashboard
EOF

    # 获取访问令牌
    DASHBOARD_TOKEN=$(kubectl -n kubernetes-dashboard create token admin-user)

    echo -e "${GREEN}[INFO] Dashboard安装完成!${NC}"
    echo -e "${YELLOW}访问令牌:${NC}"
    echo "$DASHBOARD_TOKEN"
    echo -e "${YELLOW}访问命令:${NC}"
    echo "kubectl proxy"
    echo -e "然后访问: http://localhost:8001/api/v1/namespaces/kubernetes-dashboard/services/https:kubernetes-dashboard:/proxy/"
}

# 安装Metrics Server
install_metrics_server() {
    echo -e "${GREEN}[INFO] 安装Metrics Server...${NC}"

    kubectl apply -f https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml

    # 修改参数以兼容某些环境
    kubectl patch deployment metrics-server -n kube-system --type=json \
      -p='[{"op": "add", "path": "/spec/template/spec/containers/0/args/-", "value": "--kubelet-insecure-tls"}]'

    echo -e "${GREEN}[INFO] Metrics Server安装完成!${NC}"
}

# 安装Istio
install_istio() {
    echo -e "${GREEN}[INFO] 安装Istio...${NC}"

    curl -L https://istio.io/downloadIstio | sh -
    cd istio-*
    export PATH=$PWD/bin:$PATH
    istioctl install --set profile=demo -y

    # 启用自动sidecar注入
    kubectl label namespace default istio-injection=enabled

    echo -e "${GREEN}[INFO] Istio安装完成!${NC}"
}

# 加入工作节点
join_worker() {
    if [ -z "$MASTER_IP" ] || [ -z "$TOKEN" ] || [ -z "$TOKEN_HASH" ]; then
        echo -e "${RED}错误: 工作节点需要--master-ip, --token和--token-hash参数${NC}"
        exit 1
    fi

    echo -e "${GREEN}[INFO] 加入Kubernetes集群...${NC}"
    kubeadm join $MASTER_IP:6443 --token $TOKEN --discovery-token-ca-cert-hash sha256:$TOKEN_HASH
}

# 主函数
main() {
    check_root
    detect_os

    # 解析参数
    while [ $# -gt 0 ]; do
        case "$1" in
            master|worker)
                ROLE=$1
                ;;
            --k8s-version)
                K8S_VERSION=$2
                shift
                ;;
            --pod-network-cidr)
                POD_NETWORK_CIDR=$2
                shift
                ;;
            --service-cidr)
                SERVICE_CIDR=$2
                shift
                ;;
            --master-ip)
                MASTER_IP=$2
                shift
                ;;
            --token)
                TOKEN=$2
                shift
                ;;
            --token-hash)
                TOKEN_HASH=$2
                shift
                ;;
            --container-runtime)
                CONTAINER_RUNTIME=$2
                shift
                ;;
            --install-dashboard)
                INSTALL_DASHBOARD=true
                ;;
            --install-metrics)
                INSTALL_METRICS=true
                ;;
            --install-istio)
                INSTALL_ISTIO=true
                ;;
            -h|--help)
                usage
                ;;
            *)
                echo -e "${RED}未知参数: $1${NC}"
                usage
                ;;
        esac
        shift
    done

    if [ -z "$ROLE" ]; then
        echo -e "${RED}错误: 必须指定角色(master或worker)${NC}"
        usage
    fi

    # 执行安装步骤
    install_tools
    disable_swap
    configure_kernel
    install_container_runtime
    install_kube_packages

    if [ "$ROLE" = "master" ]; then
        init_master
        install_network_plugin

        if [ "$INSTALL_DASHBOARD" = true ]; then
            install_dashboard
        fi

        if [ "$INSTALL_METRICS" = true ]; then
            install_metrics_server
        fi

        if [ "$INSTALL_ISTIO" = true ]; then
            install_istio
        fi

    elif [ "$ROLE" = "worker" ]; then
        join_worker
    fi

    echo -e "${GREEN}[SUCCESS] Kubernetes $ROLE节点安装完成!${NC}"
}

main "$@"

使用说明

1. 主节点安装

```bash

基本安装

sudo ./install_k8s.sh master

自定义参数安装

sudo ./install_k8s.sh master \ --k8s-version 1.28.0 \ --pod-network-cidr 10.244.0.0/16 \ --service-cidr 10.96.0.0/12 \ --container-runtime contain