aws(学习笔记第十二课) 使用AWS的RDS-MySQL

aws(学习笔记第十二课)

  • 使用AWS的RDS

学习内容:

  • AWS的RDS-MySQL

1. 使用AWS的RDS

  1. 什么是RDS
    RDS就是Relation Database Service的缩写,是AWS提供的托管关系型数据库系统。让用户能够在 AWS Cloud 云中更轻松地设置、操作和扩展关系数据库。

    • 数据库和web server服务器下的架构
  2. 使用Cloudformation构建RDS以及AutoScaling
    注意mail地址的时候,要指定postgresql@163.com的形式,要用@加上domain的形式,否则,下面的wordpressinstall会报错,导致该cloudformation创建失败

    • Cloudformation代码

      json 复制代码
      {
      	"AWSTemplateFormatVersion": "2010-09-09",
      	"Description": "AWS in Action: chapter 9",
      	"Parameters": {
      		"KeyName": {
      			"Description": "Key Pair name",
      			"Type": "AWS::EC2::KeyPair::KeyName",
      			"Default": "my-cli-key"
      		},
      		"BlogTitle": {
      			"Description": "The title of the blog.",
      			"Type": "String",
      			"Default": "Amazon Web Services in Action - Example"
      		},
      		"AdminUsername": {
      			"Description": "A username for admin.",
      			"Type": "String",
      			"Default": "admin"
      		},
      		"AdminPassword": {
      			"Description": "A password for admin",
      			"Type": "String",
      			"NoEcho": "true"
      		},
      		"AdminEMail": {
      			"Description": "The email address of the administrator.",
      			"Type": "String"
      		}
      	},
      	"Mappings": {
      		"EC2RegionMap": {
      			"ap-northeast-1": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-cbf90ecb"},
      			"ap-southeast-1": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-68d8e93a"},
      			"ap-southeast-2": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-fd9cecc7"},
      			"eu-central-1": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-a8221fb5"},
      			"eu-west-1": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-a10897d6"},
      			"sa-east-1": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-b52890a8"},
      			"us-east-1": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-1ecae776"},
      			"us-west-1": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-d114f295"},
      			"us-west-2": {"AmazonLinuxAMIHVMEBSBacked64bit": "ami-e7527ed7"}
      		}
      	},
      	"Resources": {
      		"VPC": {
      			"Type": "AWS::EC2::VPC",
      			"Properties": {
      				"CidrBlock": "172.31.0.0/16",
      				"EnableDnsHostnames": "true"
      			}
      		},
      		"InternetGateway": {
      			"Type": "AWS::EC2::InternetGateway",
      			"Properties": {
      			}
      		},
      		"VPCGatewayAttachment": {
      			"Type": "AWS::EC2::VPCGatewayAttachment",
      			"Properties": {
      				"VpcId": {"Ref": "VPC"},
      				"InternetGatewayId": {"Ref": "InternetGateway"}
      			}
      		},
      		"SubnetA": {
      			"Type": "AWS::EC2::Subnet",
      			"Properties": {
      				"AvailabilityZone": {"Fn::Select": ["0", {"Fn::GetAZs": ""}]},
      				"CidrBlock": "172.31.38.0/24",
      				"VpcId": {"Ref": "VPC"}
      			}
      		},
      		"SubnetB": {
      			"Type": "AWS::EC2::Subnet",
      			"Properties": {
      				"AvailabilityZone": {"Fn::Select": ["1", {"Fn::GetAZs": ""}]},
      				"CidrBlock": "172.31.37.0/24",
      				"VpcId": {"Ref": "VPC"}
      			}
      		},
      		"RouteTable": {
      			"Type": "AWS::EC2::RouteTable",
      			"Properties": {
      				"VpcId": {"Ref": "VPC"}
      			}
      		},
      		"RouteTableAssociationA": {
      			"Type": "AWS::EC2::SubnetRouteTableAssociation",
      			"Properties": {
      				"SubnetId": {"Ref": "SubnetA"},
      				"RouteTableId": {"Ref": "RouteTable"}
      			}
      		},
      		"RouteTableAssociationB": {
      			"Type": "AWS::EC2::SubnetRouteTableAssociation",
      			"Properties": {
      				"SubnetId": {"Ref": "SubnetB"},
      				"RouteTableId": {"Ref": "RouteTable"}
      			}
      		},
      		"RoutePublicNATToInternet": {
      			"Type": "AWS::EC2::Route",
      			"Properties": {
      				"RouteTableId": {"Ref": "RouteTable"},
      				"DestinationCidrBlock": "0.0.0.0/0",
      				"GatewayId": {"Ref": "InternetGateway"}
      			},
      			"DependsOn": "VPCGatewayAttachment"
      		},
      		"NetworkAcl": {
      			"Type": "AWS::EC2::NetworkAcl",
      			"Properties": {
      				"VpcId": {"Ref": "VPC"}
      			}
      		},
      		"SubnetNetworkAclAssociationA": {
      			"Type": "AWS::EC2::SubnetNetworkAclAssociation",
      			"Properties": {
      				"SubnetId": {"Ref": "SubnetA"},
      				"NetworkAclId": {"Ref": "NetworkAcl"}
      			}
      		},
      		"SubnetNetworkAclAssociationB": {
      			"Type": "AWS::EC2::SubnetNetworkAclAssociation",
      			"Properties": {
      				"SubnetId": {"Ref": "SubnetB"},
      				"NetworkAclId": {"Ref": "NetworkAcl"}
      			}
      		},
      		"NetworkAclEntryIngress": {
      			"Type": "AWS::EC2::NetworkAclEntry",
      			"Properties": {
      				"NetworkAclId": {"Ref": "NetworkAcl"},
      				"RuleNumber": "100",
      				"Protocol": "-1",
      				"RuleAction": "allow",
      				"Egress": "false",
      				"CidrBlock": "0.0.0.0/0"
      			}
      		},
      		"NetworkAclEntryEgress": {
      			"Type": "AWS::EC2::NetworkAclEntry",
      			"Properties": {
      				"NetworkAclId": {"Ref": "NetworkAcl"},
      				"RuleNumber": "100",
      				"Protocol": "-1",
      				"RuleAction": "allow",
      				"Egress": "true",
      				"CidrBlock": "0.0.0.0/0"
      			}
      		},
      		"LoadBalancer": {
      			"Type": "AWS::ElasticLoadBalancing::LoadBalancer",
      			"Properties": {
      				"Subnets": [{"Ref": "SubnetA"}, {"Ref": "SubnetB"}],
      				"LoadBalancerName": "awsinaction-elb",
      				"Listeners": [{
      					"InstancePort": "80",
      					"InstanceProtocol": "HTTP",
      					"LoadBalancerPort": "80",
      					"Protocol": "HTTP"
      				}],
      				"HealthCheck": {
      					"HealthyThreshold": "2",
      					"Interval": "5",
      					"Target": "TCP:80",
      					"Timeout": "3",
      					"UnhealthyThreshold": "2"
      				},
      				"SecurityGroups": [{"Ref": "LoadBalancerSecurityGroup"}],
      				"Scheme": "internet-facing"
      			},
      			"DependsOn": "VPCGatewayAttachment"
      		},
      		"LoadBalancerSecurityGroup": {
      			"Type": "AWS::EC2::SecurityGroup",
      			"Properties": {
      				"GroupDescription": "awsinaction-elb-sg",
      				"VpcId": {"Ref": "VPC"},
      				"SecurityGroupIngress": [{
      					"CidrIp": "0.0.0.0/0",
      					"FromPort": 80,
      					"IpProtocol": "tcp",
      					"ToPort": 80
      				}]
      			}
      		},
      		"WebServerSecurityGroup": {
      			"Type": "AWS::EC2::SecurityGroup",
      			"Properties": {
      				"GroupDescription": "awsinaction-sg",
      				"VpcId": {"Ref": "VPC"},
      				"SecurityGroupIngress": [{
      					"CidrIp": "0.0.0.0/0",
      					"FromPort": 22,
      					"IpProtocol": "tcp",
      					"ToPort": 22
      				}, {
      					"FromPort": 80,
      					"IpProtocol": "tcp",
      					"SourceSecurityGroupId": {"Ref": "LoadBalancerSecurityGroup"},
      					"ToPort": 80
      				}]
      			}
      		},
      		"DatabaseSecurityGroup": {
      			"Type": "AWS::EC2::SecurityGroup",
      			"Properties": {
      				"GroupDescription": "awsinaction-db-sg",
      				"VpcId": {"Ref": "VPC"},
      				"SecurityGroupIngress": [{
      					"IpProtocol": "tcp",
      					"FromPort": "3306",
      					"ToPort": "3306",
      					"SourceSecurityGroupId": {"Ref": "WebServerSecurityGroup"}
      				}]
      			}
      		},
      		"Database": {
      			"Type": "AWS::RDS::DBInstance",
      			"DeletionPolicy": "Delete",
      			"Properties": {
      				"AllocatedStorage": "25",
      				"DBInstanceClass": "db.t3.medium",
      				"DBInstanceIdentifier": "awsinaction-db",
      				"DBName": "wordpress",
      				"Engine": "MySQL",
      				"EngineVersion": "5.7",
      				"MasterUsername": "wordpress",
      				"MasterUserPassword": "wordpress",
      				"VPCSecurityGroups": [{"Fn::GetAtt": ["DatabaseSecurityGroup", "GroupId"]}],
      				"DBSubnetGroupName": {"Ref": "DBSubnetGroup"}
      			},
      			"DependsOn": "VPCGatewayAttachment"
      		},
      		"DBSubnetGroup" : {
      			"Type" : "AWS::RDS::DBSubnetGroup",
      			"Properties" : {
      				"DBSubnetGroupDescription" : "DB subnet group",
      				"SubnetIds": [{"Ref": "SubnetA"}, {"Ref": "SubnetB"}]
      			}
      		},
      		"LaunchTemplate": {
      			"Type": "AWS::EC2::LaunchTemplate",
      			"Metadata": {
      				"AWS::CloudFormation::Init": {
      					"config": {
      						"packages": {
      							"yum": {
      								"php": [],
      								"php-mysql": [],
      								"mysql": [],
      								"httpd": []
      							}
      						},
      						"sources": {
      							"/var/www/html": "https://wordpress.org/wordpress-4.2.4.tar.gz"
      						},
      						"files": {
      							"/tmp/config": {
      								"content": {"Fn::Join": ["", [
      									"#!/bin/bash -ex\n",
      									"cp /var/www/html/wordpress/wp-config-sample.php /var/www/html/wordpress/wp-config.php\n",
      									"sed -i \"s/'database_name_here'/'wordpress'/g\" wp-config.php\n",
      									"sed -i \"s/'username_here'/'wordpress'/g\" wp-config.php\n",
      									"sed -i \"s/'password_here'/'wordpress'/g\" wp-config.php\n",
      									"sed -i \"s/'localhost'/'", {"Fn::GetAtt": ["Database", "Endpoint.Address"]}, "'/g\" wp-config.php\n",
      									"chmod -R 777 wp-content/ \n",
      									"curl -O https://raw.githubusercontent.com/AWSinAction/builds/gh-pages/phar/wp-cli.phar \n",
      									"php wp-cli.phar core install --url=\"", {"Fn::GetAtt": ["LoadBalancer", "DNSName"]}, "/wordpress\" --title=\"", {"Ref": "BlogTitle"}, "\" --admin_user=\"", {"Ref": "AdminUsername"}, "\" --admin_password=\"", {"Ref": "AdminPassword"}, "\" --admin_email=\"", {"Ref": "AdminEMail"}, "\" \n"								]]},
      								"mode": "000500",
      								"owner": "root",
      								"group": "root"
      							}
      						},
      						"commands": {
      							"01_config": {
      								"command": "/tmp/config",
      								"cwd": "/var/www/html/wordpress"
      							}
      						},
      						"services": {
      							"sysvinit": {
      								"httpd": {
      									"enabled": "true",
      									"ensureRunning": "true"
      								}
      							}
      						}
      					}
      				}
      			},
      			"Properties": {
      				"LaunchTemplateName": "LaunchTemplate",
      				"LaunchTemplateData":{
      					"EbsOptimized": false,
      					"ImageId": {"Fn::FindInMap": ["EC2RegionMap", {"Ref": "AWS::Region"}, "AmazonLinuxAMIHVMEBSBacked64bit"]},
      					"InstanceType": "t2.micro",
      					"NetworkInterfaces":[
      						{
      							"DeviceIndex":0,
      							"AssociatePublicIpAddress":true,
      							"Groups":[
      								{"Ref": "WebServerSecurityGroup"}
      							],
      							"DeleteOnTermination":true
      						}
      					],
      					"KeyName": {"Ref": "KeyName"},
      					"UserData": {"Fn::Base64": {"Fn::Join": ["", [
      						"#!/bin/bash -ex\n",
      						"yum update -y aws-cfn-bootstrap\n",
      						"/opt/aws/bin/cfn-init -v --stack ", {"Ref": "AWS::StackName"}, " --resource LaunchTemplate --region ", {"Ref": "AWS::Region"}, "\n",
      						"/opt/aws/bin/cfn-signal -e $? --stack ", {"Ref": "AWS::StackName"}, " --resource AutoScalingGroup --region ", {"Ref": "AWS::Region"}, "\n"
      					]]}}}
      			}
      		},
      		"AutoScalingGroup": {
      			"Type": "AWS::AutoScaling::AutoScalingGroup",
      			"Properties": {
      				"LoadBalancerNames": [{"Ref": "LoadBalancer"}],
      				"LaunchTemplate" : {"LaunchTemplateId" : {"Ref" : "LaunchTemplate"},"Version" : {"Fn::GetAtt" : ["LaunchTemplate","LatestVersionNumber"]}},
      				"MinSize": "2",
      				"MaxSize": "2",
      				"DesiredCapacity": "2",
      				"VPCZoneIdentifier": [{"Ref": "SubnetA"}, {"Ref": "SubnetB"}]
      			},
      			"CreationPolicy": {
      				"ResourceSignal": {
      					"Timeout": "PT10M"
      				}
      			},
      			"DependsOn": "VPCGatewayAttachment"
      		}
      	},
      	"Outputs": {
      		"URL": {
      			"Value": {"Fn::Join": ["", ["http://", {"Fn::GetAtt": ["LoadBalancer", "DNSName"]}, "/wordpress"]]},
      			"Description": "Wordpress URL"
      		}
      	}
      }
  3. 逐步解析整个Cloudformation

    • 定义VPC以及两个subnet

      • 代码

        json 复制代码
        "VPC": {
        			"Type": "AWS::EC2::VPC",
        			"Properties": {
        				"CidrBlock": "172.31.0.0/16",
        				"EnableDnsHostnames": "true"
        			}
        		},
        		"InternetGateway": {
        			"Type": "AWS::EC2::InternetGateway",
        			"Properties": {
        			}
        		},
        		"VPCGatewayAttachment": {
        			"Type": "AWS::EC2::VPCGatewayAttachment",
        			"Properties": {
        				"VpcId": {"Ref": "VPC"},
        				"InternetGatewayId": {"Ref": "InternetGateway"}
        			}
        		},
        		"SubnetA": {
        			"Type": "AWS::EC2::Subnet",
        			"Properties": {
        				"AvailabilityZone": {"Fn::Select": ["0", {"Fn::GetAZs": ""}]},
        				"CidrBlock": "172.31.38.0/24",
        				"VpcId": {"Ref": "VPC"}
        			}
        		},
        		"SubnetB": {
        			"Type": "AWS::EC2::Subnet",
        			"Properties": {
        				"AvailabilityZone": {"Fn::Select": ["1", {"Fn::GetAZs": ""}]},
        				"CidrBlock": "172.31.37.0/24",
        				"VpcId": {"Ref": "VPC"}
        			}
        		},
      • 系统构成

      • 代码解析

        • 定义了一个VPC
        • 定义了一个InternetGateway,并将其attachVPC上。
        • 定义了两个subnet,其中每个subnet都在一个AvailabilityZoneAZ)里面。
    • 定义RouterRouteTable,并附加在两个subnet

      • 代码

        json 复制代码
        "RouteTable": {
        			"Type": "AWS::EC2::RouteTable",
        			"Properties": {
        				"VpcId": {"Ref": "VPC"}
        			}
        		},
        		"RouteTableAssociationA": {
        			"Type": "AWS::EC2::SubnetRouteTableAssociation",
        			"Properties": {
        				"SubnetId": {"Ref": "SubnetA"},
        				"RouteTableId": {"Ref": "RouteTable"}
        			}
        		},
        		"RouteTableAssociationB": {
        			"Type": "AWS::EC2::SubnetRouteTableAssociation",
        			"Properties": {
        				"SubnetId": {"Ref": "SubnetB"},
        				"RouteTableId": {"Ref": "RouteTable"}
        			}
        		},
        		"RoutePublicNATToInternet": {
        			"Type": "AWS::EC2::Route",
        			"Properties": {
        				"RouteTableId": {"Ref": "RouteTable"},
        				"DestinationCidrBlock": "0.0.0.0/0",
        				"GatewayId": {"Ref": "InternetGateway"}
        			},
        			"DependsOn": "VPCGatewayAttachment"
        		},
        • 对应的系统构成

          注意,"DependsOn": "VPCGatewayAttachment",因为需要0.0.0.0路由到InternetGateway的时候,需要VPC attach到InternetGateway作为先行条件,所以加上DependsOn
        • 代码解析
          • 定义一个RouteTable,指定VPC
          • 将这个RouteTable附加到subnet A
          • 将这个RouteTable附加到subnet B
          • 给路由表RouteTable加上路由RouteEC2如果想要访问Internet网络,那么经由InternetGateway
    • 定义RouterRouteTable,并附加在两个subnet

      • 代码

        json 复制代码
        		"NetworkAcl": {
        			"Type": "AWS::EC2::NetworkAcl",
        			"Properties": {
        				"VpcId": {"Ref": "VPC"}
        			}
        		},
        		"SubnetNetworkAclAssociationA": {
        			"Type": "AWS::EC2::SubnetNetworkAclAssociation",
        			"Properties": {
        				"SubnetId": {"Ref": "SubnetA"},
        				"NetworkAclId": {"Ref": "NetworkAcl"}
        			}
        		},
        		"SubnetNetworkAclAssociationB": {
        			"Type": "AWS::EC2::SubnetNetworkAclAssociation",
        			"Properties": {
        				"SubnetId": {"Ref": "SubnetB"},
        				"NetworkAclId": {"Ref": "NetworkAcl"}
        			}
        		},
        		"NetworkAclEntryIngress": {
        			"Type": "AWS::EC2::NetworkAclEntry",
        			"Properties": {
        				"NetworkAclId": {"Ref": "NetworkAcl"},
        				"RuleNumber": "100",
        				"Protocol": "-1",
        				"RuleAction": "allow",
        				"Egress": "false",
        				"CidrBlock": "0.0.0.0/0"
        			}
        		},
        		"NetworkAclEntryEgress": {
        			"Type": "AWS::EC2::NetworkAclEntry",
        			"Properties": {
        				"NetworkAclId": {"Ref": "NetworkAcl"},
        				"RuleNumber": "100",
        				"Protocol": "-1",
        				"RuleAction": "allow",
        				"Egress": "true",
        				"CidrBlock": "0.0.0.0/0"
        			}
        		},
      • 系统构成

      • 代码解析

        • 定义一个NetworkAcl
        • 定义两个SubnetNetworkAclAssociation,一个是从0.0.0.0入站(egress = true)的网络都开放,另一个是从subnet出站(egress = true)到0.0.0.0的都开放
    • 定义一个LoadBalancer以及security group

      • 代码

        json 复制代码
        "LoadBalancer": {
        			"Type": "AWS::ElasticLoadBalancing::LoadBalancer",
        			"Properties": {
        				"Subnets": [{"Ref": "SubnetA"}, {"Ref": "SubnetB"}],
        				"LoadBalancerName": "awsinaction-elb",
        				"Listeners": [{
        					"InstancePort": "80",
        					"InstanceProtocol": "HTTP",
        					"LoadBalancerPort": "80",
        					"Protocol": "HTTP"
        				}],
        				"HealthCheck": {
        					"HealthyThreshold": "2",
        					"Interval": "5",
        					"Target": "TCP:80",
        					"Timeout": "3",
        					"UnhealthyThreshold": "2"
        				},
        				"SecurityGroups": [{"Ref": "LoadBalancerSecurityGroup"}],
        				"Scheme": "internet-facing"
        			},
        			"DependsOn": "VPCGatewayAttachment"
        		},
        		"LoadBalancerSecurityGroup": {
        			"Type": "AWS::EC2::SecurityGroup",
        			"Properties": {
        				"GroupDescription": "awsinaction-elb-sg",
        				"VpcId": {"Ref": "VPC"},
        				"SecurityGroupIngress": [{
        					"CidrIp": "0.0.0.0/0",
        					"FromPort": 80,
        					"IpProtocol": "tcp",
        					"ToPort": 80
        				}]
        			}
        		},
      • 系统构成

      • 代码解析

        • 定义一个LoadBalancer
        • 定义一个LoadBalancerSecurityGroup,开放internetLoadBalancer80端口访问
    • 定义WebServerSecurityGroup

      • 代码

        json 复制代码
        "WebServerSecurityGroup": {
        			"Type": "AWS::EC2::SecurityGroup",
        			"Properties": {
        				"GroupDescription": "awsinaction-sg",
        				"VpcId": {"Ref": "VPC"},
        				"SecurityGroupIngress": [{
        					"CidrIp": "0.0.0.0/0",
        					"FromPort": 22,
        					"IpProtocol": "tcp",
        					"ToPort": 22
        				}, {
        					"FromPort": 80,
        					"IpProtocol": "tcp",
        					"SourceSecurityGroupId": {"Ref": "LoadBalancerSecurityGroup"},
        					"ToPort": 80
        				}]
        			}
        		},
      • 系统构成

        • 代码解析
          • 定义一个WebServerSecurityGroup
          • 允许internet访问22端口
          • 只允许LoadBalancerSecurityGroup所属的主机访问80端口
    • 定义数据库和数据所在的security group

      • 代码

        json 复制代码
        "DatabaseSecurityGroup": {
        			"Type": "AWS::EC2::SecurityGroup",
        			"Properties": {
        				"GroupDescription": "awsinaction-db-sg",
        				"VpcId": {"Ref": "VPC"},
        				"SecurityGroupIngress": [{
        					"IpProtocol": "tcp",
        					"FromPort": "3306",
        					"ToPort": "3306",
        					"SourceSecurityGroupId": {"Ref": "WebServerSecurityGroup"}
        				}]
        			}
        		},
        		"Database": {
        			"Type": "AWS::RDS::DBInstance",
        			"DeletionPolicy": "Delete",
        			"Properties": {
        				"AllocatedStorage": "25",
        				"DBInstanceClass": "db.t3.medium",
        				"DBInstanceIdentifier": "awsinaction-db",
        				"DBName": "wordpress",
        				"Engine": "MySQL",
        				"EngineVersion": "5.7",
        				"MasterUsername": "wordpress",
        				"MasterUserPassword": "wordpress",
        				"VPCSecurityGroups": [{"Fn::GetAtt": ["DatabaseSecurityGroup", "GroupId"]}],
        				"DBSubnetGroupName": {"Ref": "DBSubnetGroup"}
        			},
        			"DependsOn": "VPCGatewayAttachment"
        		},
        		"DBSubnetGroup" : {
        			"Type" : "AWS::RDS::DBSubnetGroup",
        			"Properties" : {
        				"DBSubnetGroupDescription" : "DB subnet group",
        				"SubnetIds": [{"Ref": "SubnetA"}, {"Ref": "SubnetB"}]
        			}
        		},
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