【k8s】使用Terraform一键部署EKS集群

本文适用范文

• 使用AWS海外账号
• 对aws、terraform、k8s有一定的了解
• 新建一个独立的VPC

Terraform简介

terraform是一个云端的资源编排工具，官方对自己的定位：Terraform is an open-source infrastructure as code software。
类似的，在AWS云上有CloudFormation，我们选择terraform是因为它更加的通用，能够同时管理AWS云，Azure云，阿里云等常见的云服务。
使用方式详见：https://registry.terraform.io/namespaces/hashicorp

前置条件

• 有一个AWS海外账号，并且拥有管理员权限
• 执行脚本的服务器以赋予角色，角色拥有administrator权限（实际用不到这么高的权限，仅为了演示，未做最小权限配置）
• 服务器已安装terraform程序（安装方式见terraform官网）
• 服务器已安装awscli和kubectl

说明

为了方便阅读，tf脚本按照aws资源类型拆分（实际上将所有配置打包到一个tf脚本里也能执行）

脚本内容

脚本中已标记注释，这里就不解释每段的含义了。

main.tf

各位客官根据自己需要，修改此脚本中的参数。其他脚本均不需要修改

# author zhenglisai
# 使用当前脚本所在服务器角色权限
provider "aws" {
  region = "us-west-2"
}
# 获取当前可用区
data "aws_availability_zones" "available" {
  state = "available"
}
# 本地参数，下面参数均可根据自己需要修改。
locals {
  # EKS集群名
  cluster_name = "tf-cluster-zhenglisai"
  # EKS集群角色名
  cluster_role_name = "tf-cluster-zhenglisai"
  # EKS计算节点名
  node_name = "tf-node-zhenglisai"
  # EKS计算节点角色
  node_role_name = "tf-node-zhenglisai"
  # EKS计算节点使用的启动模板名
  launch_template_name = "tf-launch_template-zhenglisai"
  # image_id每个区域不同，此ID仅适用于us-west-2区域，其他区域的镜像请参见AWS文档
  launch_template_image_id = "ami-0cb182e3037115aa0"
  # EKS计算节点使用的实例类型
  launch_template_instance_type = "t3.small"
  # 服务器登录密钥，需要提前在EC2的密钥管理中配置好
  launch_template_key_name = "你的密钥名"
  # EKS集群使用的VPC网段
  vpc_cidr_block = "10.2.0.0/16"
  # EKS集群使用的子网网段
  subnet_1_cidr_block = "10.2.0.0/20"
  # EKS集群使用的子网网段
  subnet_2_cidr_block = "10.2.16.0/20"
}

eks.tf

# author zhenglisai
# 集群
resource "aws_eks_cluster" "eks-cluster" {
  name     = local.cluster_name
  role_arn = aws_iam_role.eks-cluster.arn
  vpc_config {
    subnet_ids = [aws_subnet.subnet_1.id, aws_subnet.subnet_2.id]
    security_group_ids = [aws_security_group.eks-cluster.id]
  }
}
# 计算节点
resource "aws_eks_node_group" "eks-node" {
  cluster_name  = aws_eks_cluster.eks-cluster.name
  node_group_name = local.node_name
  node_role_arn = aws_iam_role.eks-node.arn
  subnet_ids    = [aws_subnet.subnet_1.id, aws_subnet.subnet_2.id]
  scaling_config {
    desired_size = 2
    max_size     = 3
    min_size     = 1
  }
  launch_template {
    version = aws_launch_template.eks-template.latest_version
    id = aws_launch_template.eks-template.id
  }
}

ec2.tf

# author zhenglisai
resource "aws_launch_template" "eks-template" {
  name = local.launch_template_name
  image_id = local.launch_template_image_id
  instance_type = local.launch_template_instance_type
  key_name = local.launch_template_key_name
  vpc_security_group_ids = [aws_security_group.eks-node.id]
  user_data = base64encode("#!/bin/bash\n/etc/eks/bootstrap.sh ${aws_eks_cluster.eks-cluster.name}")
}

iam.tf

# author zhenglisai
data "aws_iam_policy" "AmazonEKSClusterPolicy" {
  name = "AmazonEKSClusterPolicy"
}
data "aws_iam_policy" "AmazonEKSWorkerNodePolicy" {
  name = "AmazonEKSWorkerNodePolicy"
}
data "aws_iam_policy" "AmazonEC2ContainerRegistryReadOnly" {
  name = "AmazonEC2ContainerRegistryReadOnly"
}
data "aws_iam_policy" "AmazonEKS_CNI_Policy" {
  name = "AmazonEKS_CNI_Policy"
}
data "aws_iam_policy_document" "ec2-instance" {
  statement {
    actions = ["sts:AssumeRole"]

    principals {
      type        = "Service"
      identifiers = ["ec2.amazonaws.com"]
    }
  }
}
data "aws_iam_policy_document" "eks-instance" {
  statement {
    actions = ["sts:AssumeRole"]

    principals {
      type        = "Service"
      identifiers = ["eks.amazonaws.com"]
    }
  }
}
resource "aws_iam_role" "eks-cluster" {
  name = local.cluster_role_name
  assume_role_policy = data.aws_iam_policy_document.eks-instance.json
  managed_policy_arns = [data.aws_iam_policy.AmazonEKSClusterPolicy.arn]
}
resource "aws_iam_role" "eks-node" {
  name = local.node_role_name
  assume_role_policy = data.aws_iam_policy_document.ec2-instance.json
  managed_policy_arns = [data.aws_iam_policy.AmazonEC2ContainerRegistryReadOnly.arn, data.aws_iam_policy.AmazonEKS_CNI_Policy.arn, data.aws_iam_policy.AmazonEKSWorkerNodePolicy.arn]
}

securitygroup.tf

# author zhenglisai
resource "aws_security_group" "eks-cluster" {
  name        = "eks-cluster"
  description = "Allow local vpc"
  vpc_id      = aws_vpc.eks.id
  ingress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = [local.vpc_cidr_block]
  }
  egress {
    from_port = 0
    to_port = 0
    protocol = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }
  tags = {
    Name = "eks-cluster"
  }
}
resource "aws_security_group" "eks-node" {
  name        = "eks-node"
  description = "Allow local vpc"
  vpc_id      = aws_vpc.eks.id
  ingress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = [local.vpc_cidr_block]
  }
  egress {
    from_port = 0
    to_port = 0
    protocol = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }
  tags = {
    Name = "eks-node"
  }
}

vpc.tf

# author zhenglisai
resource "aws_vpc" "eks" {
  cidr_block = local.vpc_cidr_block
  enable_dns_hostnames = "true"
  tags = {
    Name = "eks"
  }
}

# 定义Subnet子网
resource "aws_subnet" "subnet_1" {
  vpc_id = aws_vpc.eks.id
  map_public_ip_on_launch = true
  cidr_block = local.subnet_1_cidr_block
  availability_zone = data.aws_availability_zones.available.names[0]
  tags = {
    Name = "subnet_1"
    "kubernetes.io/role/elb" = "1"
  }
}
resource "aws_subnet" "subnet_2" {
  vpc_id = aws_vpc.eks.id
  map_public_ip_on_launch = true
  cidr_block = local.subnet_2_cidr_block
  availability_zone = data.aws_availability_zones.available.names[1]
  tags = {
    Name = "subnet_2"
    "kubernetes.io/role/elb" = "1"
  }
}
# 创建公网接口
resource "aws_internet_gateway" "igw-eks" {
  vpc_id = aws_vpc.eks.id
  tags = {
    Name = "igw-eks"
  }
}
# 修改路由表
data "aws_route_table" "route_table_eks" {
  vpc_id = aws_vpc.eks.id
  filter {
    name = "association.main"
    values = [true]
  }
}
resource "aws_route" "route_table_eks" {
  route_table_id = data.aws_route_table.route_table_eks.id
  destination_cidr_block = "0.0.0.0/0"
  gateway_id = aws_internet_gateway.igw-eks.id
}

将以上文件保存在一个目录中，比如eks_demo目录

开始执行

进入目录，并初始化terraform资源

cd eks_demo && terraform init

初始化完成后，开始执行terraform部署

terraform apply

执行后会开始检查资源，等待检查完毕后，确认输入yes开始部署

整个部署过程大概需要持续15分钟左右
部署完成后，配置kubectl权限，之后便可与EKS开始交互

删除资源

实验结束后，如果不需要保留资源，在tf脚本所在目录执行

terraform destroy

即可删除所有terraform创建的资源