aws cloudformation -resource property error - aws-cloudformation

Question

I have defined my parameters like this:
{
"PrivateSubnets":{
"Description":"db subnetlist",
"Type": "List<AWS::EC2::Subnet::Id>"
},
"VPCLIST": {
"Description": "VPC list",
"Type": "List<AWS::EC2::VPC::Id>"
}
}
and referring the above parameters in "resources" section like below:
"InstanceSecurityGroup" : {
"Type" : "AWS::EC2::SecurityGroup",
"Properties" : {
"VpcId" : {"Ref": "VPCLIST"} ,
"GroupDescription" : "Enable 3306/80/SSH access via port 22"
}
and while executing this I am getting the below error.
AWS::EC2::SecurityGroup InstanceSecurityGroup "Value of property VpcId must be of type String"
Note: I have only default VPC available which is not taken as string? any solutions to this issue...

Answer 1

The correct way is make this change:
{
"PrivateSubnets": {
"Description":"db subnetlist",
"Type": "AWS::EC2::Subnet::Id"
},
"VPCLIST": {
"Description": "VPC list",
"Type": "AWS::EC2::VPC::Id"
}
}

Answer 2

The Security Groups requires the VpcId to be a string, the property is an array list, So you need to change the property to Type: String, or use the
Fn::Select function.
{ "Fn::Select" : [ 0, VPCLIST ] }
List – An array of VPC IDs
{
"Type" : "AWS::EC2::SecurityGroup",
"Properties" : {
"GroupName" : String,
"GroupDescription" : String,
"SecurityGroupEgress" : [ Security Group Rule, ... ],
"SecurityGroupIngress" : [ Security Group Rule, ... ],
"Tags" : [ Resource Tag, ... ],
"VpcId" : String
}
}
http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-ec2-security-group.html