cdk/cloudformation如何理解哪个子网是PRIVATE还是PUBLIC

Question

我在AWS中有三个子网。

一个是公共的，因为它有互联网网关

另外两个则不然。

然而，当cdk合成，有模板cdk.context.json

它判断每三个子网是Public

然而，另外两个实际上是Isolated(没有NAT网关和公共IP(

为什么cdk认为他们是Public？？

"vpc-provider:account=678100XXXXXX:filter.vpc-id=vpc-0867d6797e62dd78b:region=ap-northeast-1:returnAsymmetricSubnets=true": {
"vpcId": "vpc-0867d6797e62dd78b",
"vpcCidrBlock": "10.0.0.0/24",
"availabilityZones": [],
"subnetGroups": [
{
"name": "Public",
"type": "Public",
"subnets": [
{
"subnetId": "subnet-0b5985476dee1f20c",
"cidr": "10.0.0.0/25",
"availabilityZone": "ap-northeast-1c",
"routeTableId": "rtb-02a749d8d4415bbfb"
},
{
"subnetId": "subnet-0fdd37150bfff91f0",
"cidr": "10.0.0.128/26",
"availabilityZone": "ap-northeast-1c",
"routeTableId": "rtb-02a749d8d4415bbfb"
},
{
"subnetId": "subnet-085c85398f27adbfd",
"cidr": "10.0.0.192/26",
"availabilityZone": "ap-northeast-1d",
"routeTableId": "rtb-02a749d8d4415bbfb"
}
]
}
]
}
}

Answer 1

子网是公用的还是专用的仅由其路由表决定。公用子网将具有到互联网网关的路由表，而专用子网则不会。相反，私有子网可能有到NAT网关的路由，但这仍然不能使它们成为公共子网。