VPC Subnet Module

Create any number of subnets across 1, 2, or 3 zones in a single VPC.

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Table of Contents

1. Module Variables
2. Subnet Variable
3. Outputs
4. Example Usage

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Module Variables

Name	Type	Description	Sensitive	Default
prefix	string	The prefix that you would like to append to your resources
region	string	The region to which to deploy the VPC
resource_group_id	string	ID of the resource group where subnets will be provisioned		null
tags	list(string)	List of Tags for the resource created		null
vpc_id	string	ID of the VPC where subnets will be created
use_manual_address_prefixes	bool	True if using manual address prefix creation. If false, address prefixes will be created in the VPC automatically		false
prepend_prefix_to_network_acl_names	bool	Add the prefix to network acl names when looking them up from network_acls variable.		true
network_acls	list( object({ id = string name = string }) )	List of ACLs to be used for subnets.		[]
public_gateways	object({ zone-1 = string zone-2 = string zone-3 = string })	Map of public gatways		{ zone-1 = null zone-2 = null zone-3 = null }

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Subnet Variable

List of subnets for the vpc. For each item in each array, a subnet will be created. Items can be either CIDR blocks or total ipv4 addressess. Public Gateways will be enabled only in zones where a gateway has been created.

  type = object({
    zone-1 = list(object({
      name           = string         # Name of the subnet
      cidr           = string         # CIDR block
      public_gateway = optional(bool) # Use public gateway
      acl_name       = string         # Name of network ACL to use. Will only be attached if name is found in var.network_acls
    }))
    zone-2 = list(object({
      name           = string
      cidr           = string
      public_gateway = optional(bool)
      acl_name       = string
    }))
    zone-3 = list(object({
      name           = string
      cidr           = string
      public_gateway = optional(bool)
      acl_name       = string
    }))
  })

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Outputs

• subnet_zone_list

output "subnet_zone_list" {
  description = "A list containing subnet IDs and subnet zones"
  value = [
    for subnet in ibm_is_subnet.subnet : {
      name = subnet.name
      id   = subnet.id
      zone = subnet.zone
      cidr = subnet.ipv4_cidr_block
    }
  ]
}

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Example Usage

module "subnets" {
  source                      = "github.com/Cloud-Schematics/vpc-subnet-module"
  prefix                      = var.prefix
  region                      = var.region
  tags                        = var.tags
  resource_group_id           = data.ibm_resource_group.resource_group.id
  vpc_id                      = ibm_is_vpc.vpc.id
  use_manual_address_prefixes = var.use_manual_address_prefixes
  network_acls                = module.network_acls.acls
  public_gateways             = module.public_gateways.gateways
  subnets                     = var.subnets
  depends_on                  = [module.address_prefixes] # Force dependecy on address prefixes to prevent creation errors
}