如何引用已有的子网和安全组参数，并在YAML cloudformation模板中引用?

Question

如何引用已存在的子网和安全组参数，并在YAML cloudformation模板中引用?

我尝试将子网和安全组的参数从硬编码ID更改为变量，但得到错误"属性SubnetId的值必须是字符串"

Parametres:
PublicSecurityGroup:
Description: WebSecurityGroup
#Type: String
Type: AWS::EC2::SecurityGroup::Id
#Default: sg-081d3059c58edb3b6
PublicSubnet:
Description: Web/PublicSecurityGroup
#Type : String
#Default: subnet-0b3ea12c33b327f0a
Type: 'List<AWS::EC2::Subnet::Id>'

Resources:
WebInstance: 
Type: AWS::EC2::Instance
Properties:
KeyName:
Ref: KeyName
InstanceType:
!FindInMap [
EnvironmentToInstanceType,
!Ref EnvironmentInstanceType,
InstanceType,
]
ImageId: !Ref ImageId
# AvailabilityZone: !Ref AvailabilityZone
#SubnetId: !Ref PublicSubnet
SubnetId:
- Ref: PublicSubnet
SecurityGroupIds:
- Ref: PublicSecurityGroup

Answer 1

AWS::EC2::Instance只能在一个子网中，不能在多个子网中。所以你必须指定一个子网，而不是子网列表。

Parametres:
PublicSecurityGroup:
Description: WebSecurityGroup
#Type: String
Type: AWS::EC2::SecurityGroup::Id
#Default: sg-081d3059c58edb3b6
PublicSubnet:
Description: Web/PublicSecurityGroup
#Type : String
#Default: subnet-0b3ea12c33b327f0a
Type: 'AWS::EC2::Subnet::Id'

Resources:
WebInstance: 
Type: AWS::EC2::Instance
Properties:
KeyName:
Ref: KeyName
InstanceType:
!FindInMap [
EnvironmentToInstanceType,
!Ref EnvironmentInstanceType,
InstanceType,
]
ImageId: !Ref ImageId
# AvailabilityZone: !Ref AvailabilityZone
#SubnetId: !Ref PublicSubnet
SubnetId: !Ref PublicSubnet
SecurityGroupIds:
- Ref: PublicSecurityGroup