背景

SLB + ECS + RDS 是企业级应用的基础搭配，在小型应用场景下这三款产品成为了架构的核心组件。

基本结构如上图所示，创建一组ECS实例并挂在到SLB下面，然后创建一个ECS实例，同时把ECS的IP加入到访问白名单。作为应用方，您只需要根据业务类型和特点预估一下ECS的数量即可，其余的事情可以帮您一键完成。

创建的资源包括

• ALIYUN::ECS::InstanceGroup

  • 创建一组相同配置的ECS.

注意：如果每台ECS的转发权重一样的话，可以采用本文的方式挂载到SLB，否则您可以并设置不同的权重值。

• ALIYUN::SLB::LoadBalancer

  • 创建一个负载均衡

• ALIYUN::SLB::Listener

  • 配置监听

• ALIYUN::SLB::BackendServerAttachment

  • 挂载ECS到负载均衡

• ALIYUN::RDS::DBInstance

  • 创建RDS实例

有关RDS更多配置请参考

步骤详解

• step1: 创建一组ECS实例，配置为2核4G(ecs.s2.large), 选择非IO优化的普通云盘，选择公共镜像，同时创建一个安全组。ECS数量的上线根据具体的业务场景来设置，本例设置默认值为2。

"ecsInstanceGroup": {      "Properties": {        "ImageId": "centos7u2_64_40G_cloudinit_20160520.raw",        "InstanceType": "ecs.s2.large",        "MaxAmount": {          "Ref": "EcsMaxAmount"        },        "MinAmount": 2,        "SecurityGroupId": {          "Fn::GetAtt": [            "securityGroup",            "SecurityGroupId"          ]        }      },      "Type": "ALIYUN::ECS::InstanceGroup"    },"securityGroup": {      "Properties": {        "SecurityGroupEgress": [          {            "DestCidrIp": "0.0.0.0/0",            "IpProtocol": "all",            "NicType": "internet",            "PortRange": "-1/-1",            "Priority": 1          }        ],        "SecurityGroupIngress": [          {            "IpProtocol": "all",            "NicType": "internet",            "PortRange": "-1/-1",            "Priority": 1,            "SourceCidrIp": "0.0.0.0/0"          }        ],        "SecurityGroupName": {          "Ref": "SecurityGroupName"        }      },      "Type": "ALIYUN::ECS::SecurityGroup"    }

• step2: 创建负载均衡，设置端口映射为80 -> 8080

"LoadBalancer": {      "Properties": {        "AddressType": "internet",        "InternetChargeType": "paybytraffic",        "LoadBalancerName": "createByRos"      },      "Type": "ALIYUN::SLB::LoadBalancer"    },    "CreateListener": {      "Type": "ALIYUN::SLB::Listener",      "Properties": {          "LoadBalancerId": {"Ref": "LoadBalancer"},          "ListenerPort": "80",          "BackendServerPort": 8080,          "Bandwidth": 1,          "Protocol": "http",          "HealthCheck": {              "HealthyThreshold": 3,              "UnhealthyThreshold": 3,              "Interval": 2,              "Timeout": 5,              "HttpCode": "http_2xx,http_3xx,http_4xx,http_5xx"          },          "Scheduler": "wrr"      }    }

• step3: 挂载ECS到SLB, 设置相同的权重

"Attachment": {      "Properties": {        "BackendServerList":         {          "Fn::GetAtt": [            "ecsInstanceGroup",            "InstanceIds"          ]        },        "LoadBalancerId": {          "Ref": "LoadBalancer"        }      },      "Type": "ALIYUN::SLB::BackendServerAttachment"    }

• step4: 创建RDS实例，同时设置访问白名单

"RDSInstance": {      "Properties": {        "ConnectionMode": "Safty",        "DBInstanceClass": "rds.mys2.large",        "DBInstanceDescription": "createByRos",        "DBInstanceNetType": "Intranet",        "DBInstanceStorage": "100",        "Engine": "MySQL",        "EngineVersion": "5.6",        "SecurityIPList": {          "Fn::GetAtt": [            "ecsInstanceGroup",            "PrivateIps"          ]        }      },      "Type": "ALIYUN::RDS::DBInstance"    }