# Amazon Elastic File System 샘플 템플릿
<a name="quickref-efs"></a>

Amazon Elastic File System(Amazon EFS)는 Amazon Elastic Compute Cloud(Amazon EC2) 인스턴스에 대한 파일 스토리지 서비스입니다. Amazon EFS를 사용하면 파일을 추가하고 제거할 때마다 스토리지 용량이 자동으로 확장 및 축소되므로 애플리케이션에서 스토리지가 필요할 때 확보할 수 있습니다.

다음 샘플 템플릿은 Amazon EFS 파일 시스템과 연결되는 EC2 인스턴스를 Auto Scaling 그룹에 배포합니다. 인스턴스를 파일 시스템과 연결하기 위해 인스턴스에서 cfn-init 헬퍼 스크립트를 실행합니다. 그러면 헬퍼 스크립트에서 `nfs-utils` yum 패키지를 다운로드하여 설치하고, 새 디렉터리를 생성한 다음 파일 시스템의 DNS 이름을 사용하여 해당 디렉터리에 파일 시스템을 탑재합니다. 파일 시스템의 DNS 이름은 Amazon EC2 인스턴스의 가용 영역에서 탑재 대상의 IP 주소를 확인합니다. DNS 이름 구조에 대한 자세한 내용을 알아보려면 *Amazon Elastic File System User Guide*(Amazon Elastic File System 사용 설명서)의 [Mounting File Systems](https://docs.aws.amazon.com/efs/latest/ug/mounting-fs.html)(EFS 파일 시스템 탑재)를 참조하세요.

네트워크 파일 시스템 활동을 측정하기 위해 템플릿에 사용자 지정 Amazon CloudWatch 지표가 포함되어 있습니다. 또한 템플릿은 VPC, 서브넷 및 보안 그룹을 생성합니다. 인스턴스가 파일 시스템과 통신하도록 허용하려면 VPC에서 DNS를 활성화하고 탑재 대상과 EC2 인스턴스가 동일한 가용 영역(AZ)에 있어야 합니다. 가용 영역은 서브넷에 의해 지정됩니다.

탑재 대상의 보안 그룹은 TCP 포트 2049에 대한 네트워크 연결을 활성화합니다. NFSv4 클라이언트가 파일 시스템을 탑재하려면 네트워크 연결이 필요합니다. EC2 인스턴스 및 탑재 대상의 보안 그룹에 대한 자세한 내용을 알아보려면 [https://docs.aws.amazon.com/efs/latest/ug/](https://docs.aws.amazon.com/efs/latest/ug/)(Amazon Elastic File System 사용 설명서)의 [Security](https://docs.aws.amazon.com/efs/latest/ug/security-considerations.html)(보안)를 참조하세요.

**참고**  
탑재 대상을 업데이트하여 대체될 경우 연결된 파일 시스템을 사용하는 인스턴스 또는 애플리케이션이 중단될 수 있습니다. 그러면 작성한 커밋되지 않은 내용이 손실될 수 있습니다. 중단을 방지하려면 원하는 용량을 0으로 설정하여 탑재 대상을 업데이트할 때 인스턴스를 중지합니다. 그러면 탑재 대상이 삭제되기 이전에 인스턴스에서 파일 시스템의 탑재를 해제할 수 있습니다. 탑재 업데이트가 완료된 이후에 원하는 용량을 설정하여 후속 업데이트에서 인스턴스를 시작합니다.

## JSON
<a name="quickref-efs-example-1.json"></a>

```
{
  "AWSTemplateFormatVersion": "2010-09-09",
  "Description": "This template creates an Amazon EFS file system and mount target and associates it with Amazon EC2 instances in an Auto Scaling group. **WARNING** This template creates Amazon EC2 instances and related resources. You will be billed for the AWS resources used if you create a stack from this template.",
  "Parameters": {
    "InstanceType" : {
      "Description" : "WebServer EC2 instance type",
      "Type" : "String",
      "Default" : "t2.small",
      "AllowedValues" : [ 
        "t1.micro", 
        "t2.nano", 
        "t2.micro", 
        "t2.small", 
        "t2.medium", 
        "t2.large", 
        "m1.small", 
        "m1.medium", 
        "m1.large", 
        "m1.xlarge", 
        "m2.xlarge", 
        "m2.2xlarge", 
        "m2.4xlarge", 
        "m3.medium", 
        "m3.large", 
        "m3.xlarge", 
        "m3.2xlarge", 
        "m4.large", 
        "m4.xlarge", 
        "m4.2xlarge", 
        "m4.4xlarge", 
        "m4.10xlarge", 
        "c1.medium", 
        "c1.xlarge", 
        "c3.large", 
        "c3.xlarge", 
        "c3.2xlarge", 
        "c3.4xlarge", 
        "c3.8xlarge", 
        "c4.large", 
        "c4.xlarge", 
        "c4.2xlarge", 
        "c4.4xlarge", 
        "c4.8xlarge", 
        "g2.2xlarge", 
        "g2.8xlarge", 
        "r3.large", 
        "r3.xlarge", 
        "r3.2xlarge", 
        "r3.4xlarge", 
        "r3.8xlarge", 
        "i2.xlarge", 
        "i2.2xlarge", 
        "i2.4xlarge", 
        "i2.8xlarge", 
        "d2.xlarge", 
        "d2.2xlarge", 
        "d2.4xlarge", 
        "d2.8xlarge", 
        "hi1.4xlarge", 
        "hs1.8xlarge", 
        "cr1.8xlarge", 
        "cc2.8xlarge", 
        "cg1.4xlarge"
      ],
      "ConstraintDescription" : "must be a valid EC2 instance type."
    },
    "KeyName": {
      "Type": "AWS::EC2::KeyPair::KeyName",
      "Description": "Name of an existing EC2 key pair to enable SSH access to the EC2 instances"
    },
    "AsgMaxSize": {
      "Type": "Number",
      "Description": "Maximum size and initial desired capacity of Auto Scaling Group",
      "Default": "2"
    },
    "SSHLocation" : {
      "Description" : "The IP address range that can be used to connect to the EC2 instances by using SSH",
      "Type": "String",
      "MinLength": "9",
      "MaxLength": "18",
      "Default": "0.0.0.0/0",
      "AllowedPattern": "(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})/(\\d{1,2})",
      "ConstraintDescription": "must be a valid IP CIDR range of the form x.x.x.x/x."
    },
    "VolumeName" : {
      "Description" : "The name to be used for the EFS volume",
      "Type": "String",
      "MinLength": "1",
      "Default": "myEFSvolume"
    },
    "MountPoint" : {
      "Description" : "The Linux mount point for the EFS volume",
      "Type": "String",
      "MinLength": "1",
      "Default": "myEFSvolume"
    }
  },
  "Mappings" : {
    "AWSInstanceType2Arch" : {
      "t1.micro"    : { "Arch" : "HVM64"  },
      "t2.nano"     : { "Arch" : "HVM64"  },
      "t2.micro"    : { "Arch" : "HVM64"  },
      "t2.small"    : { "Arch" : "HVM64"  },
      "t2.medium"   : { "Arch" : "HVM64"  },
      "t2.large"    : { "Arch" : "HVM64"  },
      "m1.small"    : { "Arch" : "HVM64"  },
      "m1.medium"   : { "Arch" : "HVM64"  },
      "m1.large"    : { "Arch" : "HVM64"  },
      "m1.xlarge"   : { "Arch" : "HVM64"  },
      "m2.xlarge"   : { "Arch" : "HVM64"  },
      "m2.2xlarge"  : { "Arch" : "HVM64"  },
      "m2.4xlarge"  : { "Arch" : "HVM64"  },
      "m3.medium"   : { "Arch" : "HVM64"  },
      "m3.large"    : { "Arch" : "HVM64"  },
      "m3.xlarge"   : { "Arch" : "HVM64"  },
      "m3.2xlarge"  : { "Arch" : "HVM64"  },
      "m4.large"    : { "Arch" : "HVM64"  },
      "m4.xlarge"   : { "Arch" : "HVM64"  },
      "m4.2xlarge"  : { "Arch" : "HVM64"  },
      "m4.4xlarge"  : { "Arch" : "HVM64"  },
      "m4.10xlarge" : { "Arch" : "HVM64"  },
      "c1.medium"   : { "Arch" : "HVM64"  },
      "c1.xlarge"   : { "Arch" : "HVM64"  },
      "c3.large"    : { "Arch" : "HVM64"  },
      "c3.xlarge"   : { "Arch" : "HVM64"  },
      "c3.2xlarge"  : { "Arch" : "HVM64"  },
      "c3.4xlarge"  : { "Arch" : "HVM64"  },
      "c3.8xlarge"  : { "Arch" : "HVM64"  },
      "c4.large"    : { "Arch" : "HVM64"  },
      "c4.xlarge"   : { "Arch" : "HVM64"  },
      "c4.2xlarge"  : { "Arch" : "HVM64"  },
      "c4.4xlarge"  : { "Arch" : "HVM64"  },
      "c4.8xlarge"  : { "Arch" : "HVM64"  },
      "g2.2xlarge"  : { "Arch" : "HVMG2"  },
      "g2.8xlarge"  : { "Arch" : "HVMG2"  },
      "r3.large"    : { "Arch" : "HVM64"  },
      "r3.xlarge"   : { "Arch" : "HVM64"  },
      "r3.2xlarge"  : { "Arch" : "HVM64"  },
      "r3.4xlarge"  : { "Arch" : "HVM64"  },
      "r3.8xlarge"  : { "Arch" : "HVM64"  },
      "i2.xlarge"   : { "Arch" : "HVM64"  },
      "i2.2xlarge"  : { "Arch" : "HVM64"  },
      "i2.4xlarge"  : { "Arch" : "HVM64"  },
      "i2.8xlarge"  : { "Arch" : "HVM64"  },
      "d2.xlarge"   : { "Arch" : "HVM64"  },
      "d2.2xlarge"  : { "Arch" : "HVM64"  },
      "d2.4xlarge"  : { "Arch" : "HVM64"  },
      "d2.8xlarge"  : { "Arch" : "HVM64"  },
      "hi1.4xlarge" : { "Arch" : "HVM64"  },
      "hs1.8xlarge" : { "Arch" : "HVM64"  },
      "cr1.8xlarge" : { "Arch" : "HVM64"  },
      "cc2.8xlarge" : { "Arch" : "HVM64"  }
    },
    "AWSRegionArch2AMI" : {
      "us-east-1"        : {"HVM64" : "ami-0ff8a91507f77f867", "HVMG2" : "ami-0a584ac55a7631c0c"},
      "us-west-2"        : {"HVM64" : "ami-a0cfeed8", "HVMG2" : "ami-0e09505bc235aa82d"},
      "us-west-1"        : {"HVM64" : "ami-0bdb828fd58c52235", "HVMG2" : "ami-066ee5fd4a9ef77f1"},
      "eu-west-1"        : {"HVM64" : "ami-047bb4163c506cd98", "HVMG2" : "ami-0a7c483d527806435"},
      "eu-west-2"        : {"HVM64" : "ami-f976839e", "HVMG2" : "NOT_SUPPORTED"},
      "eu-west-3"        : {"HVM64" : "ami-0ebc281c20e89ba4b", "HVMG2" : "NOT_SUPPORTED"},
      "eu-central-1"     : {"HVM64" : "ami-0233214e13e500f77", "HVMG2" : "ami-06223d46a6d0661c7"},
      "ap-northeast-1"   : {"HVM64" : "ami-06cd52961ce9f0d85", "HVMG2" : "ami-053cdd503598e4a9d"},
      "ap-northeast-2"   : {"HVM64" : "ami-0a10b2721688ce9d2", "HVMG2" : "NOT_SUPPORTED"},
      "ap-northeast-3"   : {"HVM64" : "ami-0d98120a9fb693f07", "HVMG2" : "NOT_SUPPORTED"},
      "ap-southeast-1"   : {"HVM64" : "ami-08569b978cc4dfa10", "HVMG2" : "ami-0be9df32ae9f92309"},
      "ap-southeast-2"   : {"HVM64" : "ami-09b42976632b27e9b", "HVMG2" : "ami-0a9ce9fecc3d1daf8"},
      "ap-south-1"       : {"HVM64" : "ami-0912f71e06545ad88", "HVMG2" : "ami-097b15e89dbdcfcf4"},
      "us-east-2"        : {"HVM64" : "ami-0b59bfac6be064b78", "HVMG2" : "NOT_SUPPORTED"},
      "ca-central-1"     : {"HVM64" : "ami-0b18956f", "HVMG2" : "NOT_SUPPORTED"},
      "sa-east-1"        : {"HVM64" : "ami-07b14488da8ea02a0", "HVMG2" : "NOT_SUPPORTED"},
      "cn-north-1"       : {"HVM64" : "ami-0a4eaf6c4454eda75", "HVMG2" : "NOT_SUPPORTED"},
      "cn-northwest-1"   : {"HVM64" : "ami-6b6a7d09", "HVMG2" : "NOT_SUPPORTED"}
    }
  },
  "Resources": {
    "CloudWatchPutMetricsRole" : {
      "Type"  : "AWS::IAM::Role",
      "Properties" : {
          "AssumeRolePolicyDocument" : {
              "Statement" : [ {
                  "Effect" : "Allow",
                  "Principal" : {
                      "Service" : [ "ec2.amazonaws.com" ]
                  },
                  "Action" : [ "sts:AssumeRole" ]
              } ]
          },
          "Path" : "/"
      }
    },
    "CloudWatchPutMetricsRolePolicy" : {
        "Type" : "AWS::IAM::Policy",
        "Properties" : {
            "PolicyName" : "CloudWatch_PutMetricData",
            "PolicyDocument" : {
              "Version": "2012-10-17",		 	 	 
              "Statement": [
                {
                  "Sid": "CloudWatchPutMetricData",
                  "Effect": "Allow",
                  "Action": ["cloudwatch:PutMetricData"],
                  "Resource": ["*"]
                }
              ]
            },
            "Roles" : [ { "Ref" : "CloudWatchPutMetricsRole" } ]
        }
    },
    "CloudWatchPutMetricsInstanceProfile" : {
      "Type" : "AWS::IAM::InstanceProfile",
      "Properties" : {
        "Path" : "/",
        "Roles" : [ { "Ref" : "CloudWatchPutMetricsRole" } ]
      }
    },
    "VPC": {
      "Type": "AWS::EC2::VPC",
      "Properties": {
        "EnableDnsSupport" : "true",
        "EnableDnsHostnames" : "true",
        "CidrBlock": "10.0.0.0/16",
        "Tags": [ {"Key": "Application", "Value": { "Ref": "AWS::StackId"} } ]
      }
    },
    "InternetGateway" : {
      "Type" : "AWS::EC2::InternetGateway",
      "Properties" : {
        "Tags" : [
          { "Key" : "Application", "Value" : { "Ref" : "AWS::StackName" } },
          { "Key" : "Network", "Value" : "Public" }
        ]
      }
    },
    "GatewayToInternet" : {
      "Type" : "AWS::EC2::VPCGatewayAttachment",
      "Properties" : {
        "VpcId" : { "Ref" : "VPC" },
        "InternetGatewayId" : { "Ref" : "InternetGateway" }
      }
    },
    "RouteTable":{
      "Type":"AWS::EC2::RouteTable",
      "Properties":{
        "VpcId": {"Ref":"VPC"}
      }
    },
    "SubnetRouteTableAssoc": {
      "Type" : "AWS::EC2::SubnetRouteTableAssociation",
      "Properties" : {
        "RouteTableId" : {"Ref":"RouteTable"},
        "SubnetId" : {"Ref":"Subnet"}
      }
    },
    "InternetGatewayRoute": {
        "Type":"AWS::EC2::Route",
        "Properties":{
            "DestinationCidrBlock":"0.0.0.0/0",
            "RouteTableId":{"Ref":"RouteTable"},
            "GatewayId":{"Ref":"InternetGateway"}
        }
    },
    "Subnet": {
      "Type": "AWS::EC2::Subnet",
      "Properties": {
        "VpcId": { "Ref": "VPC" },
        "CidrBlock": "10.0.0.0/24",
        "Tags": [ { "Key": "Application", "Value": { "Ref": "AWS::StackId" } } ]
      }
    },    
    "InstanceSecurityGroup": {
      "Type": "AWS::EC2::SecurityGroup",
      "Properties": {
        "VpcId": { "Ref": "VPC" },
        "GroupDescription": "Enable SSH access via port 22",
        "SecurityGroupIngress": [
          { "IpProtocol": "tcp", "FromPort": 22, "ToPort": 22, "CidrIp": { "Ref": "SSHLocation" } },
          { "IpProtocol": "tcp", "FromPort": 80, "ToPort": 80, "CidrIp": "0.0.0.0/0" }
         ]
      }
    },
    "MountTargetSecurityGroup": {
      "Type": "AWS::EC2::SecurityGroup",
      "Properties": {
        "VpcId": { "Ref": "VPC" },
        "GroupDescription": "Security group for mount target",
        "SecurityGroupIngress": [
          {
            "IpProtocol": "tcp",
            "FromPort": 2049,
            "ToPort": 2049,
            "CidrIp": "0.0.0.0/0"
          }
        ]
      }
    },
    "FileSystem": {
      "Type": "AWS::EFS::FileSystem",
      "Properties": {
        "PerformanceMode": "generalPurpose",
        "FileSystemTags": [
          {
            "Key": "Name",
            "Value": { "Ref" : "VolumeName" }
          }
        ]
      }
    },
    "MountTarget": {
      "Type": "AWS::EFS::MountTarget",
      "Properties": {
        "FileSystemId": { "Ref": "FileSystem" },
        "SubnetId": { "Ref": "Subnet" },
        "SecurityGroups": [ { "Ref": "MountTargetSecurityGroup" } ]        
      }
    },
    "LaunchConfiguration": {
      "Type": "AWS::AutoScaling::LaunchConfiguration",
      "Metadata" : {
        "AWS::CloudFormation::Init" : {
          "configSets" : {
            "MountConfig" : [ "setup", "mount" ]
          },
          "setup" : {
            "packages" : {
              "yum" : {
                "nfs-utils" : []
              }
            },
            "files" : {
              "/home/ec2-user/post_nfsstat" : {
                "content" : { "Fn::Join" : [ "", [
                      "#!/bin/bash\n",
                      "\n",
                      "INPUT=\"$(cat)\"\n",
                      "CW_JSON_OPEN='{ \"Namespace\": \"EFS\", \"MetricData\": [ '\n",
                      "CW_JSON_CLOSE=' ] }'\n",
                      "CW_JSON_METRIC=''\n",
                      "METRIC_COUNTER=0\n",
                      "\n",
                      "for COL in 1 2 3 4 5 6; do\n",
                      "\n",
                      " COUNTER=0\n",
                      " METRIC_FIELD=$COL\n",
                      " DATA_FIELD=$(($COL+($COL-1)))\n",
                      "\n",
                      " while read line; do\n",
                      "   if [[ COUNTER -gt 0 ]]; then\n",
                      "\n",
                      "     LINE=`echo $line | tr -s ' ' `\n",
                      "     AWS_COMMAND=\"aws cloudwatch put-metric-data --region ", { "Ref": "AWS::Region" }, "\"\n",
                      "     MOD=$(( $COUNTER % 2))\n",
                      "\n",
                      "     if [ $MOD -eq 1 ]; then\n",
                      "       METRIC_NAME=`echo $LINE | cut -d ' ' -f $METRIC_FIELD`\n",
                      "     else\n",
                      "       METRIC_VALUE=`echo $LINE | cut -d ' ' -f $DATA_FIELD`\n",
                      "     fi\n",
                      "\n",
                      "     if [[ -n \"$METRIC_NAME\" && -n \"$METRIC_VALUE\" ]]; then\n",
                      "       INSTANCE_ID=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)\n",
                      "       CW_JSON_METRIC=\"$CW_JSON_METRIC { \\\"MetricName\\\": \\\"$METRIC_NAME\\\", \\\"Dimensions\\\": [{\\\"Name\\\": \\\"InstanceId\\\", \\\"Value\\\": \\\"$INSTANCE_ID\\\"} ], \\\"Value\\\": $METRIC_VALUE },\"\n",
                      "       unset METRIC_NAME\n",
                      "       unset METRIC_VALUE\n",
                      "\n",
                      "       METRIC_COUNTER=$((METRIC_COUNTER+1))\n",
                      "       if [ $METRIC_COUNTER -eq 20 ]; then\n",
                      "         # 20 is max metric collection size, so we have to submit here\n",
                      "         aws cloudwatch put-metric-data --region ", { "Ref": "AWS::Region" }, " --cli-input-json \"`echo $CW_JSON_OPEN ${CW_JSON_METRIC%?} $CW_JSON_CLOSE`\"\n",
                      "\n",
                      "         # reset\n",
                      "         METRIC_COUNTER=0\n",
                      "         CW_JSON_METRIC=''\n",
                      "       fi\n",
                      "     fi  \n",
                      "\n",
                      "\n",
                      "\n",
                      "     COUNTER=$((COUNTER+1))\n",
                      "   fi\n",
                      "\n",
                      "   if [[ \"$line\" == \"Client nfs v4:\" ]]; then\n",
                      "     # the next line is the good stuff \n",
                      "     COUNTER=$((COUNTER+1))\n",
                      "   fi\n",
                      " done <<< \"$INPUT\"\n",
                      "done\n",
                      "\n",
                      "# submit whatever is left\n",
                      "aws cloudwatch put-metric-data --region ", { "Ref": "AWS::Region" }, " --cli-input-json \"`echo $CW_JSON_OPEN ${CW_JSON_METRIC%?} $CW_JSON_CLOSE`\""
                    ] ] },
                "mode": "000755",
                "owner": "ec2-user",
                "group": "ec2-user"
              },
              "/home/ec2-user/crontab" : {
                "content" : { "Fn::Join" : [ "", [
                  "* * * * * /usr/sbin/nfsstat | /home/ec2-user/post_nfsstat\n"
                ] ] },
                "owner": "ec2-user",
                "group": "ec2-user"
              }
            },
            "commands" : {
              "01_createdir" : {
                "command" : {"Fn::Join" : [ "", [ "mkdir /", { "Ref" : "MountPoint" }]]}
              }
            }
          },
          "mount" : {
            "commands" : {
              "01_mount" : {
                "command" : { "Fn::Sub": "sudo mount -t nfs4 -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2 ${FileSystem}.efs.${AWS::Region}.amazonaws.com:/ /${MountPoint}"}
              },
              "02_permissions" : {
                "command" : {"Fn::Join" : [ "", [ "chown ec2-user:ec2-user /", { "Ref" : "MountPoint" }]]}
              }
            }
          }
        }
      },
      "Properties": {
        "AssociatePublicIpAddress" : true,
        "ImageId": {
          "Fn::FindInMap": [ "AWSRegionArch2AMI", { "Ref": "AWS::Region" }, {
            "Fn::FindInMap": [ "AWSInstanceType2Arch", { "Ref": "InstanceType" }, "Arch" ]
          } ]
        },
        "InstanceType": { "Ref": "InstanceType" },
        "KeyName": { "Ref": "KeyName" },
        "SecurityGroups": [ { "Ref": "InstanceSecurityGroup" } ],
        "IamInstanceProfile" : { "Ref" : "CloudWatchPutMetricsInstanceProfile" },
        "UserData"       : { "Fn::Base64" : { "Fn::Join" : ["", [
             "#!/bin/bash -xe\n",
             "yum install -y aws-cfn-bootstrap\n",

             "/opt/aws/bin/cfn-init -v ",
             "         --stack ", { "Ref" : "AWS::StackName" },
             "         --resource LaunchConfiguration ",
             "         --configsets MountConfig ",
             "         --region ", { "Ref" : "AWS::Region" }, "\n",

             "crontab /home/ec2-user/crontab\n",

             "/opt/aws/bin/cfn-signal -e $? ",
             "         --stack ", { "Ref" : "AWS::StackName" },
             "         --resource AutoScalingGroup ",
             "         --region ", { "Ref" : "AWS::Region" }, "\n"
        ]]}}
      }
    },
    "AutoScalingGroup": {
      "Type": "AWS::AutoScaling::AutoScalingGroup",
      "DependsOn": ["MountTarget", "GatewayToInternet"],
      "CreationPolicy" : {
        "ResourceSignal" : {
          "Timeout" : "PT15M",
          "Count"   : { "Ref": "AsgMaxSize" }
        }
      },
      "Properties": {
        "VPCZoneIdentifier": [ { "Ref": "Subnet" } ],
        "LaunchConfigurationName": { "Ref": "LaunchConfiguration" },
        "MinSize": "1",
        "MaxSize": { "Ref": "AsgMaxSize" },
        "DesiredCapacity": { "Ref": "AsgMaxSize" },
        "Tags": [ {
          "Key": "Name",
          "Value": "EFS FileSystem Mounted Instance",
          "PropagateAtLaunch": "true"
        } ]
      }
    }
  },
  "Outputs" : {
    "MountTargetID" : {
      "Description" : "Mount target ID",
      "Value" :  { "Ref" : "MountTarget" }
    },
    "FileSystemID" : {
      "Description" : "File system ID",
      "Value" :  { "Ref" : "FileSystem" }
    }
  }
}
```

## YAML
<a name="quickref-efs-example-1.yaml"></a>

```
AWSTemplateFormatVersion: '2010-09-09'
Description: This template creates an Amazon EFS file system and mount target and
  associates it with Amazon EC2 instances in an Auto Scaling group. **WARNING** This
  template creates Amazon EC2 instances and related resources. You will be billed
  for the AWS resources used if you create a stack from this template.
Parameters:
  InstanceType:
    Description: WebServer EC2 instance type
    Type: String
    Default: t2.small
    AllowedValues:
      - t1.micro
      - t2.nano
      - t2.micro
      - t2.small
      - t2.medium
      - t2.large
      - m1.small
      - m1.medium
      - m1.large
      - m1.xlarge
      - m2.xlarge
      - m2.2xlarge
      - m2.4xlarge
      - m3.medium
      - m3.large
      - m3.xlarge
      - m3.2xlarge
      - m4.large
      - m4.xlarge
      - m4.2xlarge
      - m4.4xlarge
      - m4.10xlarge
      - c1.medium
      - c1.xlarge
      - c3.large
      - c3.xlarge
      - c3.2xlarge
      - c3.4xlarge
      - c3.8xlarge
      - c4.large
      - c4.xlarge
      - c4.2xlarge
      - c4.4xlarge
      - c4.8xlarge
      - g2.2xlarge
      - g2.8xlarge
      - r3.large
      - r3.xlarge
      - r3.2xlarge
      - r3.4xlarge
      - r3.8xlarge
      - i2.xlarge
      - i2.2xlarge
      - i2.4xlarge
      - i2.8xlarge
      - d2.xlarge
      - d2.2xlarge
      - d2.4xlarge
      - d2.8xlarge
      - hi1.4xlarge
      - hs1.8xlarge
      - cr1.8xlarge
      - cc2.8xlarge
      - cg1.4xlarge
    ConstraintDescription: must be a valid EC2 instance type.
  KeyName:
    Type: AWS::EC2::KeyPair::KeyName
    Description: Name of an existing EC2 key pair to enable SSH access to the ECS
      instances
  AsgMaxSize:
    Type: Number
    Description: Maximum size and initial desired capacity of Auto Scaling Group
    Default: '2'
  SSHLocation:
    Description: The IP address range that can be used to connect to the EC2 instances
      by using SSH
    Type: String
    MinLength: '9'
    MaxLength: '18'
    Default: 0.0.0.0/0
    AllowedPattern: "(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})/(\\d{1,2})"
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
  VolumeName:
    Description: The name to be used for the EFS volume
    Type: String
    MinLength: '1'
    Default: myEFSvolume
  MountPoint:
    Description: The Linux mount point for the EFS volume
    Type: String
    MinLength: '1'
    Default: myEFSvolume
Mappings:
  AWSInstanceType2Arch:
    t1.micro:
      Arch: HVM64
    t2.nano:
      Arch: HVM64
    t2.micro:
      Arch: HVM64
    t2.small:
      Arch: HVM64
    t2.medium:
      Arch: HVM64
    t2.large:
      Arch: HVM64
    m1.small:
      Arch: HVM64
    m1.medium:
      Arch: HVM64
    m1.large:
      Arch: HVM64
    m1.xlarge:
      Arch: HVM64
    m2.xlarge:
      Arch: HVM64
    m2.2xlarge:
      Arch: HVM64
    m2.4xlarge:
      Arch: HVM64
    m3.medium:
      Arch: HVM64
    m3.large:
      Arch: HVM64
    m3.xlarge:
      Arch: HVM64
    m3.2xlarge:
      Arch: HVM64
    m4.large:
      Arch: HVM64
    m4.xlarge:
      Arch: HVM64
    m4.2xlarge:
      Arch: HVM64
    m4.4xlarge:
      Arch: HVM64
    m4.10xlarge:
      Arch: HVM64
    c1.medium:
      Arch: HVM64
    c1.xlarge:
      Arch: HVM64
    c3.large:
      Arch: HVM64
    c3.xlarge:
      Arch: HVM64
    c3.2xlarge:
      Arch: HVM64
    c3.4xlarge:
      Arch: HVM64
    c3.8xlarge:
      Arch: HVM64
    c4.large:
      Arch: HVM64
    c4.xlarge:
      Arch: HVM64
    c4.2xlarge:
      Arch: HVM64
    c4.4xlarge:
      Arch: HVM64
    c4.8xlarge:
      Arch: HVM64
    g2.2xlarge:
      Arch: HVMG2
    g2.8xlarge:
      Arch: HVMG2
    r3.large:
      Arch: HVM64
    r3.xlarge:
      Arch: HVM64
    r3.2xlarge:
      Arch: HVM64
    r3.4xlarge:
      Arch: HVM64
    r3.8xlarge:
      Arch: HVM64
    i2.xlarge:
      Arch: HVM64
    i2.2xlarge:
      Arch: HVM64
    i2.4xlarge:
      Arch: HVM64
    i2.8xlarge:
      Arch: HVM64
    d2.xlarge:
      Arch: HVM64
    d2.2xlarge:
      Arch: HVM64
    d2.4xlarge:
      Arch: HVM64
    d2.8xlarge:
      Arch: HVM64
    hi1.4xlarge:
      Arch: HVM64
    hs1.8xlarge:
      Arch: HVM64
    cr1.8xlarge:
      Arch: HVM64
    cc2.8xlarge:
      Arch: HVM64
  AWSRegionArch2AMI:
    us-east-1:
      HVM64: ami-0ff8a91507f77f867
      HVMG2: ami-0a584ac55a7631c0c
    us-west-2:
      HVM64: ami-a0cfeed8
      HVMG2: ami-0e09505bc235aa82d
    us-west-1:
      HVM64: ami-0bdb828fd58c52235
      HVMG2: ami-066ee5fd4a9ef77f1
    eu-west-1:
      HVM64: ami-047bb4163c506cd98
      HVMG2: ami-0a7c483d527806435
    eu-west-2:
      HVM64: ami-f976839e
      HVMG2: NOT_SUPPORTED
    eu-west-3:
      HVM64: ami-0ebc281c20e89ba4b
      HVMG2: NOT_SUPPORTED
    eu-central-1:
      HVM64: ami-0233214e13e500f77
      HVMG2: ami-06223d46a6d0661c7
    ap-northeast-1:
      HVM64: ami-06cd52961ce9f0d85
      HVMG2: ami-053cdd503598e4a9d
    ap-northeast-2:
      HVM64: ami-0a10b2721688ce9d2
      HVMG2: NOT_SUPPORTED
    ap-northeast-3:
      HVM64: ami-0d98120a9fb693f07
      HVMG2: NOT_SUPPORTED
    ap-southeast-1:
      HVM64: ami-08569b978cc4dfa10
      HVMG2: ami-0be9df32ae9f92309
    ap-southeast-2:
      HVM64: ami-09b42976632b27e9b
      HVMG2: ami-0a9ce9fecc3d1daf8
    ap-south-1:
      HVM64: ami-0912f71e06545ad88
      HVMG2: ami-097b15e89dbdcfcf4
    us-east-2:
      HVM64: ami-0b59bfac6be064b78
      HVMG2: NOT_SUPPORTED
    ca-central-1:
      HVM64: ami-0b18956f
      HVMG2: NOT_SUPPORTED
    sa-east-1:
      HVM64: ami-07b14488da8ea02a0
      HVMG2: NOT_SUPPORTED
    cn-north-1:
      HVM64: ami-0a4eaf6c4454eda75
      HVMG2: NOT_SUPPORTED
    cn-northwest-1:
      HVM64: ami-6b6a7d09
      HVMG2: NOT_SUPPORTED
Resources:
  CloudWatchPutMetricsRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Statement:
        - Effect: Allow
          Principal:
            Service:
            - ec2.amazonaws.com
          Action:
          - sts:AssumeRole
      Path: "/"
  CloudWatchPutMetricsRolePolicy:
    Type: AWS::IAM::Policy
    Properties:
      PolicyName: CloudWatch_PutMetricData
      PolicyDocument:
        Version: '2012-10-17'
        Statement:
        - Sid: CloudWatchPutMetricData
          Effect: Allow
          Action:
          - cloudwatch:PutMetricData
          Resource:
          - "*"
      Roles:
      - Ref: CloudWatchPutMetricsRole
  CloudWatchPutMetricsInstanceProfile:
    Type: AWS::IAM::InstanceProfile
    Properties:
      Path: "/"
      Roles:
      - Ref: CloudWatchPutMetricsRole
  VPC:
    Type: AWS::EC2::VPC
    Properties:
      EnableDnsSupport: 'true'
      EnableDnsHostnames: 'true'
      CidrBlock: 10.0.0.0/16
      Tags:
      - Key: Application
        Value:
          Ref: AWS::StackId
  InternetGateway:
    Type: AWS::EC2::InternetGateway
    Properties:
      Tags:
      - Key: Application
        Value:
          Ref: AWS::StackName
      - Key: Network
        Value: Public
  GatewayToInternet:
    Type: AWS::EC2::VPCGatewayAttachment
    Properties:
      VpcId:
        Ref: VPC
      InternetGatewayId:
        Ref: InternetGateway
  RouteTable:
    Type: AWS::EC2::RouteTable
    Properties:
      VpcId:
        Ref: VPC
  SubnetRouteTableAssoc:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      RouteTableId:
        Ref: RouteTable
      SubnetId:
        Ref: Subnet
  InternetGatewayRoute:
    Type: AWS::EC2::Route
    Properties:
      DestinationCidrBlock: 0.0.0.0/0
      RouteTableId:
        Ref: RouteTable
      GatewayId:
        Ref: InternetGateway
  Subnet:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId:
        Ref: VPC
      CidrBlock: 10.0.0.0/24
      Tags:
      - Key: Application
        Value:
          Ref: AWS::StackId
  InstanceSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      VpcId:
        Ref: VPC
      GroupDescription: Enable SSH access via port 22
      SecurityGroupIngress:
      - IpProtocol: tcp
        FromPort: 22
        ToPort: 22
        CidrIp:
          Ref: SSHLocation
      - IpProtocol: tcp
        FromPort: 80
        ToPort: 80
        CidrIp: 0.0.0.0/0
  MountTargetSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      VpcId:
        Ref: VPC
      GroupDescription: Security group for mount target
      SecurityGroupIngress:
      - IpProtocol: tcp
        FromPort: 2049
        ToPort: 2049
        CidrIp: 0.0.0.0/0
  FileSystem:
    Type: AWS::EFS::FileSystem
    Properties:
      PerformanceMode: generalPurpose
      FileSystemTags:
      - Key: Name
        Value:
          Ref: VolumeName
  MountTarget:
    Type: AWS::EFS::MountTarget
    Properties:
      FileSystemId:
        Ref: FileSystem
      SubnetId:
        Ref: Subnet
      SecurityGroups:
      - Ref: MountTargetSecurityGroup
  LaunchConfiguration:
    Type: AWS::AutoScaling::LaunchConfiguration
    Metadata:
      AWS::CloudFormation::Init:
        configSets:
          MountConfig:
          - setup
          - mount
        setup:
          packages:
            yum:
              nfs-utils: []
          files:
            "/home/ec2-user/post_nfsstat":
              content: !Sub |
                #!/bin/bash

                INPUT="$(cat)"
                CW_JSON_OPEN='{ "Namespace": "EFS", "MetricData": [ '
                CW_JSON_CLOSE=' ] }'
                CW_JSON_METRIC=''
                METRIC_COUNTER=0

                for COL in 1 2 3 4 5 6; do

                 COUNTER=0
                 METRIC_FIELD=$COL
                 DATA_FIELD=$(($COL+($COL-1)))

                 while read line; do
                   if [[ COUNTER -gt 0 ]]; then

                     LINE=`echo $line | tr -s ' ' `
                     AWS_COMMAND="aws cloudwatch put-metric-data --region ${AWS::Region}"
                     MOD=$(( $COUNTER % 2))

                     if [ $MOD -eq 1 ]; then
                       METRIC_NAME=`echo $LINE | cut -d ' ' -f $METRIC_FIELD`
                     else
                       METRIC_VALUE=`echo $LINE | cut -d ' ' -f $DATA_FIELD`
                     fi

                     if [[ -n "$METRIC_NAME" && -n "$METRIC_VALUE" ]]; then
                       INSTANCE_ID=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)
                       CW_JSON_METRIC="$CW_JSON_METRIC { \"MetricName\": \"$METRIC_NAME\", \"Dimensions\": [{\"Name\": \"InstanceId\", \"Value\": \"$INSTANCE_ID\"} ], \"Value\": $METRIC_VALUE },"
                       unset METRIC_NAME
                       unset METRIC_VALUE

                       METRIC_COUNTER=$((METRIC_COUNTER+1))
                       if [ $METRIC_COUNTER -eq 20 ]; then
                         # 20 is max metric collection size, so we have to submit here
                         aws cloudwatch put-metric-data --region ${AWS::Region} --cli-input-json "`echo $CW_JSON_OPEN ${!CW_JSON_METRIC%?} $CW_JSON_CLOSE`"

                         # reset
                         METRIC_COUNTER=0
                         CW_JSON_METRIC=''
                       fi
                     fi



                     COUNTER=$((COUNTER+1))
                   fi

                   if [[ "$line" == "Client nfs v4:" ]]; then
                     # the next line is the good stuff
                     COUNTER=$((COUNTER+1))
                   fi
                 done <<< "$INPUT"
                done

                # submit whatever is left
                aws cloudwatch put-metric-data --region ${AWS::Region} --cli-input-json "`echo $CW_JSON_OPEN ${!CW_JSON_METRIC%?} $CW_JSON_CLOSE`"
              mode: '000755'
              owner: ec2-user
              group: ec2-user
            "/home/ec2-user/crontab":
              content: "* * * * * /usr/sbin/nfsstat | /home/ec2-user/post_nfsstat\n"
              owner: ec2-user
              group: ec2-user
          commands:
            01_createdir:
              command: !Sub "mkdir /${MountPoint}"
        mount:
          commands:
            01_mount:
              command: !Sub >
                mount -t nfs4 -o nfsvers=4.1 ${FileSystem}.efs.${AWS::Region}.amazonaws.com:/ /${MountPoint}
            02_permissions:
              command: !Sub "chown ec2-user:ec2-user /${MountPoint}"
    Properties:
      AssociatePublicIpAddress: true
      ImageId:
        Fn::FindInMap:
        - AWSRegionArch2AMI
        - Ref: AWS::Region
        - Fn::FindInMap:
          - AWSInstanceType2Arch
          - Ref: InstanceType
          - Arch
      InstanceType:
        Ref: InstanceType
      KeyName:
        Ref: KeyName
      SecurityGroups:
      - Ref: InstanceSecurityGroup
      IamInstanceProfile:
        Ref: CloudWatchPutMetricsInstanceProfile
      UserData:
        Fn::Base64: !Sub |
          #!/bin/bash -xe
          yum install -y aws-cfn-bootstrap
          /opt/aws/bin/cfn-init -v --stack ${AWS::StackName} --resource LaunchConfiguration --configsets MountConfig --region ${AWS::Region}
          crontab /home/ec2-user/crontab
          /opt/aws/bin/cfn-signal -e $? --stack ${AWS::StackName} --resource AutoScalingGroup --region ${AWS::Region}
  AutoScalingGroup:
    Type: AWS::AutoScaling::AutoScalingGroup
    DependsOn:
    - MountTarget
    - GatewayToInternet
    CreationPolicy:
      ResourceSignal:
        Timeout: PT15M
        Count:
          Ref: AsgMaxSize
    Properties:
      VPCZoneIdentifier:
      - Ref: Subnet
      LaunchConfigurationName:
        Ref: LaunchConfiguration
      MinSize: '1'
      MaxSize:
        Ref: AsgMaxSize
      DesiredCapacity:
        Ref: AsgMaxSize
      Tags:
      - Key: Name
        Value: EFS FileSystem Mounted Instance
        PropagateAtLaunch: 'true'
Outputs:
  MountTargetID:
    Description: Mount target ID
    Value:
      Ref: MountTarget
  FileSystemID:
    Description: File system ID
    Value:
      Ref: FileSystem
```