Using VPC in Cluster with CDK 0.32.0 does not work: Error: There are no 'Private' subnets in this VPC. Use a different VPC subnet selection

[markusl]

In CDK 0.31.0 our stack looked like this:

const vpcProps: ec2.VpcNetworkImportProps = {
  vpcId: 'vpc-xxxx',
  availabilityZones: ['eu-central-1a', 'eu-central-1b', 'eu-central-1c'],
  publicSubnetIds: ['subnet-xxxx', 'subnet-xxxx', 'subnet-xxxx'],
  privateSubnetIds: ['subnet-xxxx', 'subnet-xxxx', 'subnet-xxxx'],
};
    const cluster = ecs.Cluster.fromClusterAttributes(this, `Cluster`, {
      clusterName: clusterName,
      vpc: vpcProps,
      securityGroups: [ ]
    });

with CDK 0.32.0 we are forced to use a VPC with cluster import:

    const cluster = ecs.Cluster.fromClusterAttributes(this, `Cluster`, {
      clusterName: clusterName,
      vpc: vpcProps,
      securityGroups: [ ]
    });

which causes an error Error: There are no 'Private' subnets in this VPC. Use a different VPC subnet selection.

Somehow the cluster seems to lose the specified private subnets with this new model. Is there any workaround for this functionality?

[hoegertn]

I think the problem is that the class ImportedCluster uses the supplied property vpc as VpcAttributes to import the VPC but the type is IVpc.

[markusl]

Is this a bug in the CDK or is there a way to change the code to make it work again with the latest version?

[hoegertn]

I think it is a bug, but I managed to patch around it:

        const cluster = Cluster.fromClusterAttributes(this, 'Cluster', {
            vpc: <any>{
                vpcId: 'someid',
                availabilityZones: ['eu-central-1a', 'eu-central-1b', 'eu-central-1c'],
                publicSubnetIds: [
                    'someid',
                    'someid',
                    'someid',
                ],
            },
            clusterName: 'someid',
            securityGroups: []
        });

So I used VpcAttributes and told TypeScript to ignore the type mismatch.

[AlexCheema]

I also ran into this when using the VPC directly across stacks (in same app) on 0.31.0. The workaround was manually exporting/importing the VPC across stacks.

[EduardTheThird]

We reuse cluster for ECS Fargate services.

Importing a VPC is required to use an existing Cluster (ecs.Cluster.fromClusterAttributes).

When importing an existing VPC, ec2.Vpc.fromLookup and ec2.Vpc.fromVpcAttributes both results in the same error:

There are no 'Private' subnets in this VPC. Use a different VPC subnet selection.

This was using AWS CDK 0.32.

Previously in AWS CDK 0.31 I was able to work around this by first calling ec2.VpcNetwork.import
and entering vpcId, availabilityZones, publicSubnetIds and privateSubnetIds details.

Once the existing VPC was imported, I was able to import the cluster, without the error using:

cluster = ecs.Cluster.fromClusterAttributes(this,
                configuration.clusterName(), {
                    clusterName: configuration.clusterName(), 
                    securityGroups: [securityGroup],
                    vpc: {
                        vpcId: existingVpc.vpcId,
                        availabilityZones: existingVpc.availabilityZones,
                        privateSubnetIds: existingVpc.selectSubnets({ subnetType: SubnetType.Private }).subnetIds,
                        publicSubnetIds: existingVpc.selectSubnets({ subnetType: SubnetType.Public }).subnetIds
                    }
                });