EC2 / Client / create_subnet

create_subnet#

EC2.Client.create_subnet(**kwargs)#

Creates a subnet in the specified VPC. For an IPv4 only subnet, specify an IPv4 CIDR block. If the VPC has an IPv6 CIDR block, you can create an IPv6 only subnet or a dual stack subnet instead. For an IPv6 only subnet, specify an IPv6 CIDR block. For a dual stack subnet, specify both an IPv4 CIDR block and an IPv6 CIDR block.

A subnet CIDR block must not overlap the CIDR block of an existing subnet in the VPC. After you create a subnet, you can’t change its CIDR block.

The allowed size for an IPv4 subnet is between a /28 netmask (16 IP addresses) and a /16 netmask (65,536 IP addresses). Amazon Web Services reserves both the first four and the last IPv4 address in each subnet’s CIDR block. They’re not available for your use.

If you’ve associated an IPv6 CIDR block with your VPC, you can associate an IPv6 CIDR block with a subnet when you create it. The allowed block size for an IPv6 subnet is a /64 netmask.

If you add more than one subnet to a VPC, they’re set up in a star topology with a logical router in the middle.

When you stop an instance in a subnet, it retains its private IPv4 address. It’s therefore possible to have a subnet with no running instances (they’re all stopped), but no remaining IP addresses available.

For more information, see Subnets in the Amazon Virtual Private Cloud User Guide.

Request Syntax

response = client.create_subnet(
    TagSpecifications=[
        {
            'ResourceType': 'capacity-reservation'|'client-vpn-endpoint'|'customer-gateway'|'carrier-gateway'|'coip-pool'|'dedicated-host'|'dhcp-options'|'egress-only-internet-gateway'|'elastic-ip'|'elastic-gpu'|'export-image-task'|'export-instance-task'|'fleet'|'fpga-image'|'host-reservation'|'image'|'import-image-task'|'import-snapshot-task'|'instance'|'instance-event-window'|'internet-gateway'|'ipam'|'ipam-pool'|'ipam-scope'|'ipv4pool-ec2'|'ipv6pool-ec2'|'key-pair'|'launch-template'|'local-gateway'|'local-gateway-route-table'|'local-gateway-virtual-interface'|'local-gateway-virtual-interface-group'|'local-gateway-route-table-vpc-association'|'local-gateway-route-table-virtual-interface-group-association'|'natgateway'|'network-acl'|'network-interface'|'network-insights-analysis'|'network-insights-path'|'network-insights-access-scope'|'network-insights-access-scope-analysis'|'placement-group'|'prefix-list'|'replace-root-volume-task'|'reserved-instances'|'route-table'|'security-group'|'security-group-rule'|'snapshot'|'spot-fleet-request'|'spot-instances-request'|'subnet'|'subnet-cidr-reservation'|'traffic-mirror-filter'|'traffic-mirror-session'|'traffic-mirror-target'|'transit-gateway'|'transit-gateway-attachment'|'transit-gateway-connect-peer'|'transit-gateway-multicast-domain'|'transit-gateway-policy-table'|'transit-gateway-route-table'|'transit-gateway-route-table-announcement'|'volume'|'vpc'|'vpc-endpoint'|'vpc-endpoint-connection'|'vpc-endpoint-service'|'vpc-endpoint-service-permission'|'vpc-peering-connection'|'vpn-connection'|'vpn-gateway'|'vpc-flow-log'|'capacity-reservation-fleet'|'traffic-mirror-filter-rule'|'vpc-endpoint-connection-device-type'|'verified-access-instance'|'verified-access-group'|'verified-access-endpoint'|'verified-access-policy'|'verified-access-trust-provider'|'vpn-connection-device-type'|'vpc-block-public-access-exclusion'|'ipam-resource-discovery'|'ipam-resource-discovery-association',
            'Tags': [
                {
                    'Key': 'string',
                    'Value': 'string'
                },
            ]
        },
    ],
    AvailabilityZone='string',
    AvailabilityZoneId='string',
    CidrBlock='string',
    Ipv6CidrBlock='string',
    OutpostArn='string',
    VpcId='string',
    DryRun=True|False,
    Ipv6Native=True|False
)

Parameters:

TagSpecifications (list) –
The tags to assign to the subnet.
- (dict) –
  
  The tags to apply to a resource when the resource is being created. When you specify a tag, you must specify the resource type to tag, otherwise the request will fail.
  
  Note
  The Valid Values lists all the resource types that can be tagged. However, the action you’re using might not support tagging all of these resource types. If you try to tag a resource type that is unsupported for the action you’re using, you’ll get an error.
  - ResourceType (string) –
    
    The type of resource to tag on creation.
  - Tags (list) –
    
    The tags to apply to the resource.
    - (dict) –
      
      Describes a tag.
      - Key (string) –
        
        The key of the tag.
        
        Constraints: Tag keys are case-sensitive and accept a maximum of 127 Unicode characters. May not begin with aws:.
      - Value (string) –
        
        The value of the tag.
        
        Constraints: Tag values are case-sensitive and accept a maximum of 256 Unicode characters.
AvailabilityZone (string) –
The Availability Zone or Local Zone for the subnet.

Default: Amazon Web Services selects one for you. If you create more than one subnet in your VPC, we do not necessarily select a different zone for each subnet.

To create a subnet in a Local Zone, set this value to the Local Zone ID, for example us-west-2-lax-1a. For information about the Regions that support Local Zones, see Available Regions in the Amazon Elastic Compute Cloud User Guide.

To create a subnet in an Outpost, set this value to the Availability Zone for the Outpost and specify the Outpost ARN.
AvailabilityZoneId (string) – The AZ ID or the Local Zone ID of the subnet.
CidrBlock (string) –
The IPv4 network range for the subnet, in CIDR notation. For example, 10.0.0.0/24. We modify the specified CIDR block to its canonical form; for example, if you specify 100.68.0.18/18, we modify it to 100.68.0.0/18.

This parameter is not supported for an IPv6 only subnet.
Ipv6CidrBlock (string) –
The IPv6 network range for the subnet, in CIDR notation. The subnet size must use a /64 prefix length.

This parameter is required for an IPv6 only subnet.
OutpostArn (string) – The Amazon Resource Name (ARN) of the Outpost. If you specify an Outpost ARN, you must also specify the Availability Zone of the Outpost subnet.
VpcId (string) –
[REQUIRED]

The ID of the VPC.
DryRun (boolean) – Checks whether you have the required permissions for the action, without actually making the request, and provides an error response. If you have the required permissions, the error response is DryRunOperation. Otherwise, it is UnauthorizedOperation.
Ipv6Native (boolean) – Indicates whether to create an IPv6 only subnet.

Return type:

dict

Returns:

Response Syntax

{
    'Subnet': {
        'AvailabilityZone': 'string',
        'AvailabilityZoneId': 'string',
        'AvailableIpAddressCount': 123,
        'CidrBlock': 'string',
        'DefaultForAz': True|False,
        'EnableLniAtDeviceIndex': 123,
        'MapPublicIpOnLaunch': True|False,
        'MapCustomerOwnedIpOnLaunch': True|False,
        'CustomerOwnedIpv4Pool': 'string',
        'State': 'pending'|'available',
        'SubnetId': 'string',
        'VpcId': 'string',
        'OwnerId': 'string',
        'AssignIpv6AddressOnCreation': True|False,
        'Ipv6CidrBlockAssociationSet': [
            {
                'AssociationId': 'string',
                'Ipv6CidrBlock': 'string',
                'Ipv6CidrBlockState': {
                    'State': 'associating'|'associated'|'disassociating'|'disassociated'|'failing'|'failed',
                    'StatusMessage': 'string'
                }
            },
        ],
        'Tags': [
            {
                'Key': 'string',
                'Value': 'string'
            },
        ],
        'SubnetArn': 'string',
        'OutpostArn': 'string',
        'EnableDns64': True|False,
        'Ipv6Native': True|False,
        'PrivateDnsNameOptionsOnLaunch': {
            'HostnameType': 'ip-name'|'resource-name',
            'EnableResourceNameDnsARecord': True|False,
            'EnableResourceNameDnsAAAARecord': True|False
        }
    }
}

Response Structure

(dict) –
- Subnet (dict) –
  
  Information about the subnet.
  - AvailabilityZone (string) –
    
    The Availability Zone of the subnet.
  - AvailabilityZoneId (string) –
    
    The AZ ID of the subnet.
  - AvailableIpAddressCount (integer) –
    
    The number of unused private IPv4 addresses in the subnet. The IPv4 addresses for any stopped instances are considered unavailable.
  - CidrBlock (string) –
    
    The IPv4 CIDR block assigned to the subnet.
  - DefaultForAz (boolean) –
    
    Indicates whether this is the default subnet for the Availability Zone.
  - EnableLniAtDeviceIndex (integer) –
    
    Indicates the device position for local network interfaces in this subnet. For example, 1 indicates local network interfaces in this subnet are the secondary network interface (eth1).
  - MapPublicIpOnLaunch (boolean) –
    
    Indicates whether instances launched in this subnet receive a public IPv4 address.
  - MapCustomerOwnedIpOnLaunch (boolean) –
    
    Indicates whether a network interface created in this subnet (including a network interface created by RunInstances) receives a customer-owned IPv4 address.
  - CustomerOwnedIpv4Pool (string) –
    
    The customer-owned IPv4 address pool associated with the subnet.
  - State (string) –
    
    The current state of the subnet.
  - SubnetId (string) –
    
    The ID of the subnet.
  - VpcId (string) –
    
    The ID of the VPC the subnet is in.
  - OwnerId (string) –
    
    The ID of the Amazon Web Services account that owns the subnet.
  - AssignIpv6AddressOnCreation (boolean) –
    
    Indicates whether a network interface created in this subnet (including a network interface created by RunInstances) receives an IPv6 address.
  - Ipv6CidrBlockAssociationSet (list) –
    
    Information about the IPv6 CIDR blocks associated with the subnet.
    - (dict) –
      
      Describes an association between a subnet and an IPv6 CIDR block.
      - AssociationId (string) –
        
        The ID of the association.
      - Ipv6CidrBlock (string) –
        
        The IPv6 CIDR block.
      - Ipv6CidrBlockState (dict) –
        
        The state of the CIDR block.
        
        State (string) –
        
        The state of a CIDR block.
        
        StatusMessage (string) –
        
        A message about the status of the CIDR block, if applicable.
  - Tags (list) –
    
    Any tags assigned to the subnet.
    - (dict) –
      
      Describes a tag.
      - Key (string) –
        
        The key of the tag.
        
        Constraints: Tag keys are case-sensitive and accept a maximum of 127 Unicode characters. May not begin with aws:.
      - Value (string) –
        
        The value of the tag.
        
        Constraints: Tag values are case-sensitive and accept a maximum of 256 Unicode characters.
  - SubnetArn (string) –
    
    The Amazon Resource Name (ARN) of the subnet.
  - OutpostArn (string) –
    
    The Amazon Resource Name (ARN) of the Outpost.
  - EnableDns64 (boolean) –
    
    Indicates whether DNS queries made to the Amazon-provided DNS Resolver in this subnet should return synthetic IPv6 addresses for IPv4-only destinations.
  - Ipv6Native (boolean) –
    
    Indicates whether this is an IPv6 only subnet.
  - PrivateDnsNameOptionsOnLaunch (dict) –
    
    The type of hostnames to assign to instances in the subnet at launch. An instance hostname is based on the IPv4 address or ID of the instance.
    - HostnameType (string) –
      
      The type of hostname for EC2 instances. For IPv4 only subnets, an instance DNS name must be based on the instance IPv4 address. For IPv6 only subnets, an instance DNS name must be based on the instance ID. For dual-stack subnets, you can specify whether DNS names use the instance IPv4 address or the instance ID.
    - EnableResourceNameDnsARecord (boolean) –
      
      Indicates whether to respond to DNS queries for instance hostnames with DNS A records.
    - EnableResourceNameDnsAAAARecord (boolean) –
      
      Indicates whether to respond to DNS queries for instance hostname with DNS AAAA records.

Examples

This example creates a subnet in the specified VPC with the specified CIDR block. We recommend that you let us select an Availability Zone for you.

response = client.create_subnet(
    CidrBlock='10.0.1.0/24',
    VpcId='vpc-a01106c2',
)

print(response)

Expected Output:

{
    'Subnet': {
        'AvailabilityZone': 'us-west-2c',
        'AvailableIpAddressCount': 251,
        'CidrBlock': '10.0.1.0/24',
        'State': 'pending',
        'SubnetId': 'subnet-9d4a7b6c',
        'VpcId': 'vpc-a01106c2',
    },
    'ResponseMetadata': {
        '...': '...',
    },
}