AWS CDK - Create custom Subnets with custom CIDR blocks

 

 When you're building a VPC through AWS CDK, the Vpc construct will create the subnets automatically for you without allowing you to specify the subnet cidr blocks.

    const pizzaVPC = new CfnVPC(this, "CDKPizzaVPC", {

cidrBlock: "10.1.0.0/16",

});

If you don't want them, then use CfnVPC, this will allow you to manually create your subnets with any highlevel construct. i.e: 

    const subnet1 = new PublicSubnet(this, "CDKSubnet1", {

vpcId: pizzaVPC.ref,

availabilityZone: "us-east-1a",

cidrBlock: "10.1.0.0/24",

});

const subnet2 = new PublicSubnet(this, "CDKSubnet2", {

vpcId: pizzaVPC.ref,

availabilityZone: "us-east-1b",

cidrBlock: "10.1.2.0/24",

});