如何构建只有一个 EC2 实例的 CloudFormation 和 Elastic Beanstalk 解决方案？

Question

此直接 CloudFormation 代码 sn-p 是 https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/sample-templates-services-ap-south-1.html 中提供的示例 ElasticBeanstalk 应用程序的一部分

    "Mappings" : {
    "Region2Principal" : {
      "us-east-1"      : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "us-west-2"      : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "us-west-1"      : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "eu-west-1"      : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "eu-west-2"      : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "eu-west-3"      : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "ap-southeast-1" : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "ap-northeast-1" : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "ap-northeast-2" : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "ap-northeast-3" : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "ap-southeast-2" : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "ap-south-1"     : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "us-east-2"      : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "ca-central-1"   : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "sa-east-1"      : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "cn-north-1"     : { "EC2Principal" : "ec2.amazonaws.com.cn", "OpsWorksPrincipal" : "opsworks.amazonaws.com.cn" },
      "cn-northwest-1" : { "EC2Principal" : "ec2.amazonaws.com.cn", "OpsWorksPrincipal" : "opsworks.amazonaws.com.cn" },
      "eu-central-1"   : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" },
      "eu-north-1"     : { "EC2Principal" : "ec2.amazonaws.com", "OpsWorksPrincipal" : "opsworks.amazonaws.com" }
    }

  },

  "Conditions" : {
    "Is-EC2-VPC"     : { "Fn::Or" : [ {"Fn::Equals" : [{"Ref" : "AWS::Region"}, "eu-central-1" ]},
                                      {"Fn::Equals" : [{"Ref" : "AWS::Region"}, "cn-north-1" ]}]},
    "Is-EC2-Classic" : { "Fn::Not" : [{ "Condition" : "Is-EC2-VPC"}]}
  },

  "Resources": {
    "WebServerRole": {
      "Type": "AWS::IAM::Role",
      "Properties" : {
        "AssumeRolePolicyDocument" : {
          "Statement"  : [{
            "Effect"   : "Allow",
            "Principal": { "Service": [{ "Fn::FindInMap" : ["Region2Principal", {"Ref" : "AWS::Region"}, "EC2Principal"]}] },
            "Action"   : [ "sts:AssumeRole" ]
          } ]
        },
        "Path": "/"
      }
    },

    "WebServerRolePolicy": {
      "Type": "AWS::IAM::Policy",
      "Properties": {
        "PolicyName" : "WebServerRole",
        "PolicyDocument" : {
          "Statement"  : [ {
            "Effect"    : "Allow",
            "NotAction" : "iam:*",
            "Resource"  : "*"
          } ]
        },
        "Roles": [ { "Ref": "WebServerRole" } ]
      }
    },

    "WebServerInstanceProfile": {
      "Type": "AWS::IAM::InstanceProfile",
      "Properties": {
        "Path": "/",
        "Roles": [ { "Ref": "WebServerRole" } ]
      }
    },

    "SampleApplication": {
      "Type": "AWS::ElasticBeanstalk::Application",
      "Properties": {
        "Description": "AWS Elastic Beanstalk Sample Application"
      }
    },

    "SampleApplicationVersion" : {
      "Type" : "AWS::ElasticBeanstalk::ApplicationVersion",
      "Properties" : {
        "Description" : "Version 1.0",
        "ApplicationName" : { "Ref" : "SampleApplication" },
        "SourceBundle" : {
          "S3Bucket": { "Fn::Join" : ["-", ["cloudformation-examples", {"Ref" : "AWS::Region" }]]},
          "S3Key": "CloudFormationBeanstalkRDSExample.war"
        }
      }
    },

我在 AWS 上只有免费套餐账户，所以我不想花钱来测试它的行为方式。描述说：

警告 此模板创建一个或多个 Amazon EC2 实例和一个 Amazon Relational Database Service 数据库实例。如果您从此模板创建堆栈，您需要为使用的 AWS 资源付费。

我的问题是，如果启动会创建多少个实例？我没有看到任何限制，但Mappings 部分似乎很长，我想至少不止一个。 Conditions 有两个条目，这是否也意味着两个实例？我想找到一个只运行一个实例的解决方案，只限制区域或如何将创建的 EC2 数量限制为一个就足够了吗？

Answer 1

其实我找到了办法：

我将此解决方案作为基础解决方案：

AWSTemplateFormatVersion: '2010-09-09'
Resources:
  sampleApplication:
    Type: AWS::ElasticBeanstalk::Application
    Properties:
      Description: AWS Elastic Beanstalk Sample Application
  sampleApplicationVersion:
    Type: AWS::ElasticBeanstalk::ApplicationVersion
    Properties:
      ApplicationName:
        Ref: sampleApplication
      Description: AWS ElasticBeanstalk Sample Application Version
      SourceBundle:
        S3Bucket: !Sub "elasticbeanstalk-samples-${AWS::Region}"
        S3Key: php-newsample-app.zip
  sampleConfigurationTemplate:
    Type: AWS::ElasticBeanstalk::ConfigurationTemplate
    Properties:
      ApplicationName:
        Ref: sampleApplication
      Description: AWS ElasticBeanstalk Sample Configuration Template
      OptionSettings:
      - Namespace: aws:autoscaling:asg
        OptionName: MinSize
        Value: '2'
      - Namespace: aws:autoscaling:asg
        OptionName: MaxSize
        Value: '6'
      - Namespace: aws:elasticbeanstalk:environment
        OptionName: EnvironmentType
        Value: LoadBalanced
      SolutionStackName: 64bit Amazon Linux 2018.03 v2.8.15 running PHP 7.2
  sampleEnvironment:
    Type: AWS::ElasticBeanstalk::Environment
    Properties:
      ApplicationName:
        Ref: sampleApplication
      Description: AWS ElasticBeanstalk Sample Environment
      TemplateName:
        Ref: sampleConfigurationTemplate
      VersionLabel:
        Ref: sampleApplicationVersion

（在https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/quickref-elasticbeanstalk.html中找到）

如果我将EnvironmentType 更改为SingleInstance，我会得到我想要的单实例解决方案。

（在https://docs.aws.amazon.com/elasticbeanstalk/latest/dg/command-options-general.html#command-options-general-elasticbeanstalkenvironment中找到）

我还没有对此进行测试，但我想我可以以同样的方式删除MinSize 和MaxSize，因为这是单实例。

Answer 2

我认为您使用此模板。 https://s3-ap-south-1.amazonaws.com/cloudformation-templates-ap-south-1/ElasticBeanstalk_Simple.template

在这种情况下，它会创建一个 db.t2.small 数据库。 RDS 的 Amazon 免费套餐仅是 db.t2.micro。如果您将模板编辑为免费套餐，该警告应该会消失

更多信息在这里：https://aws.amazon.com/rds/free/