AWS CloudFormation: unable to create RDS resource with VPC assigned

Question

I am deploying my CloudFormation with an RDS resource in it. I am assigning thee VPC to it as well.

This is my template.

AWSTemplateFormatVersion: '2010-09-09'
Description: "Simple 3 tier web application template"
Parameters:
  KeyName:
    Default: 'MyanEat'
    Type: String
  VpcCidr:
    Default: '10.1.0.0/16'
    Type: String
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
  InstanceType:
    Default: 't2.micro'
    Type: String
  SSHLocation:
    Description: The IP address range that can be used to SSH to the EC2 instances
    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
  DBInstanceIdentifier:
    Type: String
  DBName:
    Type: String
  DBUsername:
    Type: String
  DBClass:
    Type: String
    Default: 'db.t2.micro'
  DBAllocatedStorage:
    Type: String
    Default: '5'
  DBPassword:
    Type: String
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:
  Vpc:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: !Ref VpcCidr
      EnableDnsHostnames: True
      EnableDnsSupport: True
  PublicSubnet1:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 0, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      MapPublicIpOnLaunch: True
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref "AWS::Region"
  DatabaseSubnet1:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 2, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref "AWS::Region"
  WebServerInstance:
    Type: AWS::EC2::Instance
    Properties:
      InstanceType: !Ref InstanceType
      KeyName: !Ref KeyName
      SubnetId: !Ref PublicSubnet1
      ImageId:
        Fn::FindInMap:
          - AWSRegionArch2AMI
          - Ref: AWS::Region
          - Fn::FindInMap:
              - AWSInstanceType2Arch
              - Ref: InstanceType
              - Arch
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref "AWS::Region"
  WebServerSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Enable HTTP access via port 80
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '80'
          ToPort: '80'
          CidrIp: 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: '22'
          ToPort: '22'
          CidrIp:
            Ref: SSHLocation
      VpcId: !Ref Vpc
  DBSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      VpcId: !Ref Vpc
      GroupDescription: Enable TCP connection on port 3306 for database connection
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '3306'
          ToPort: '3306'
          SourceSecurityGroupId: !Ref WebServerSecurityGroup
  WebDatabase:
    Type: AWS::RDS::DBInstance
    Properties:
      DBInstanceIdentifier: !Ref DBInstanceIdentifier
      DBName: !Ref DBName
      DBInstanceClass: !Ref DBClass
      AllocatedStorage: !Ref DBAllocatedStorage
      Engine: MySQL
      MasterUsername: !Ref DBUsername
      MasterUserPassword: !Ref DBPassword
      VPCSecurityGroups:
        - !Ref DBSecurityGroup

As you can see, the last resource in the template is the RDS database. I am assigning VPC to it through VPCSecurityGroups property. When I deploy my template, it is saying that creating the RDS resource is failing. If I removed it from the template and deploy it again, there is no issue at all. How can I fix it?

Failing event logs

 {
        "StackId": "arn:aws:cloudformation:eu-west-1:733553390213:stack/basicwebapp1/768498b0-cee7-11ea-8afe-06c305fba8da", 
        "EventId": "eed90a30-cee7-11ea-a999-022b3a528618", 
        "ResourceStatus": "UPDATE_ROLLBACK_IN_PROGRESS", 
        "ResourceType": "AWS::CloudFormation::Stack", 
        "Timestamp": "2020-07-26T02:30:12.795Z", 
        "ResourceStatusReason": "The following resource(s) failed to create: [DBSecurityGroup]. ", 
        "StackName": "basicwebapp1", 
        "PhysicalResourceId": "arn:aws:cloudformation:eu-west-1:733553390213:stack/basicwebapp1/768498b0-cee7-11ea-8afe-06c305fba8da", 
        "LogicalResourceId": "basicwebapp1"
    }, 
   .
   .
   .

 {
        "StackId": "arn:aws:cloudformation:eu-west-1:733553390213:stack/basicwebapp1/768498b0-cee7-11ea-8afe-06c305fba8da", 
        "EventId": "8d980c90-ceeb-11ea-ace5-02fa7ab4594c", 
        "ResourceStatus": "UPDATE_ROLLBACK_IN_PROGRESS", 
        "ResourceType": "AWS::CloudFormation::Stack", 
        "Timestamp": "2020-07-26T02:56:07.621Z", 
        "ResourceStatusReason": "The following resource(s) failed to update: [WebDatabase]. ", 
        "StackName": "basicwebapp1", 
        "PhysicalResourceId": "arn:aws:cloudformation:eu-west-1:733553390213:stack/basicwebapp1/768498b0-cee7-11ea-8afe-06c305fba8da", 
        "LogicalResourceId": "basicwebapp1"
    },
    .
    .
    .

I tried creating Subnet group for DB and assign it too.

DBSubnetGroup:
    Type: AWS::RDS::DBSubnetGroup
    Properties:
      DBSubnetGroupDescription: "Subnet Group to specify the subnets for web database"
      SubnetIds:
        - !Ref DatabaseSubnet1
        - !Ref DatabaseSubnet2
  DBSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      VpcId: !Ref Vpc
      GroupDescription: Enable TCP connection on port 3306 for database connection
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '3306'
          ToPort: '3306'
          SourceSecurityGroupId: !Ref WebServerSecurityGroup
  WebDatabase:
    Type: AWS::RDS::DBInstance
    Properties:
      DBInstanceIdentifier: !Ref DBInstanceIdentifier
      DBName: !Ref DBName
      DBInstanceClass: !Ref DBClass
      AllocatedStorage: !Ref DBAllocatedStorage
      Engine: MySQL
      MasterUsername: !Ref DBUsername
      MasterUserPassword: !Ref DBPassword
      VPCSecurityGroups:
        - !Ref DBSecurityGroup
      DBSubnetGroupName:
        - !Ref DBSubnetGroup

It is still not working. The subnets are in different AZs.

Could you put the full error? Have you tried 'dependOn' for WebDataase? — Nghia Do
Hi, @NghiaDo, I just put the logs there. Please have a look. Can you post the code, please? — Wai Yan Hein

Chris Williams Chris Williams · Accepted Answer · 2020-07-26T15:35:29

Edit

In addition the OP also have to rebuild stack as some resources were created in the wrong VPC and led to a race condition when updating the stack.

Original

I am getting the following error The DB instance and EC2 security group are in different VPCs. The DB instance is in vpc-bbda8cdf and the EC2 security group.

This is because your WebDatabase resource does not have an attached DB subnet group.

A AWS::RDS::DBSubnetGroup resource should be created containing 2 subnets (in different AZs) within the VPC.

Then in your RDS resource use the DBSubnetGroupName to specify the above resources name.

Below is an example template

AWSTemplateFormatVersion: '2010-09-09'
Description: "Simple 3 tier web application template"
Parameters:
  KeyName:
    Default: 'MyanEat'
    Type: String
  VpcCidr:
    Default: '10.1.0.0/16'
    Type: String
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
  InstanceType:
    Default: 't2.micro'
    Type: String
  SSHLocation:
    Description: The IP address range that can be used to SSH to the EC2 instances
    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
  DBInstanceIdentifier:
    Type: String
  DBName:
    Type: String
  DBUsername:
    Type: String
  DBClass:
    Type: String
    Default: 'db.t2.micro'
  DBAllocatedStorage:
    Type: String
    Default: '5'
  DBPassword:
    Type: String
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:
  Vpc:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: !Ref VpcCidr
      EnableDnsHostnames: True
      EnableDnsSupport: True
  PublicSubnet1:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 0, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      MapPublicIpOnLaunch: True
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref "AWS::Region"
  DatabaseSubnet1:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 2, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref "AWS::Region"
  DatabaseSubnet2:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 4, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      AvailabilityZone: !Select
        - 1
        - Fn::GetAZs: !Ref "AWS::Region"
  WebServerInstance:
    Type: AWS::EC2::Instance
    Properties:
      InstanceType: !Ref InstanceType
      KeyName: !Ref KeyName
      SubnetId: !Ref PublicSubnet1
      ImageId:
        Fn::FindInMap:
          - AWSRegionArch2AMI
          - Ref: AWS::Region
          - Fn::FindInMap:
              - AWSInstanceType2Arch
              - Ref: InstanceType
              - Arch
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref "AWS::Region"
  WebServerSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Enable HTTP access via port 80
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '80'
          ToPort: '80'
          CidrIp: 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: '22'
          ToPort: '22'
          CidrIp:
            Ref: SSHLocation
      VpcId: !Ref Vpc
  DBSubnetGroup:
    Type: AWS::RDS::DBSubnetGroup
    Properties:
      DBSubnetGroupDescription: "Subnet Group to specify the subnets for web database"
      SubnetIds:
        - !Ref DatabaseSubnet1
        - !Ref DatabaseSubnet2
  DBSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      VpcId: !Ref Vpc
      GroupDescription: Enable TCP connection on port 3306 for database connection
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '3306'
          ToPort: '3306'
          SourceSecurityGroupId: !Ref WebServerSecurityGroup
  WebDatabase:
    Type: AWS::RDS::DBInstance
    Properties:
      DBInstanceIdentifier: !Ref DBInstanceIdentifier
      DBName: !Ref DBName
      DBInstanceClass: !Ref DBClass
      AllocatedStorage: !Ref DBAllocatedStorage
      Engine: MySQL
      MasterUsername: !Ref DBUsername
      MasterUserPassword: !Ref DBPassword
      VPCSecurityGroups:
        - !Ref DBSecurityGroup
      DBSubnetGroupName: !Ref DBSubnetGroup

AWS CloudFormation: unable to create RDS resource with VPC assigned

1 Answers