EC2 / Client / describe_subnets

describe_subnets#

EC2.Client.describe_subnets(**kwargs)#

Describes your subnets. The default is to describe all your subnets. Alternatively, you can specify specific subnet IDs or filter the results to include only the subnets that match specific criteria.

For more information, see Subnets in the Amazon VPC User Guide.

See also: AWS API Documentation

Request Syntax

response = client.describe_subnets(
    Filters=[
        {
            'Name': 'string',
            'Values': [
                'string',
            ]
        },
    ],
    SubnetIds=[
        'string',
    ],
    NextToken='string',
    MaxResults=123,
    DryRun=True|False
)
Parameters:

  • Filters (list) –

    The filters.

    • availability-zone - The Availability Zone for the subnet. You can also use availabilityZone as the filter name.

    • availability-zone-id - The ID of the Availability Zone for the subnet. You can also use availabilityZoneId as the filter name.

    • available-ip-address-count - The number of IPv4 addresses in the subnet that are available.

    • cidr-block - The IPv4 CIDR block of the subnet. The CIDR block you specify must exactly match the subnet’s CIDR block for information to be returned for the subnet. You can also use cidr or cidrBlock as the filter names.

    • customer-owned-ipv4-pool - The customer-owned IPv4 address pool associated with the subnet.

    • default-for-az - Indicates whether this is the default subnet for the Availability Zone ( true | false). You can also use defaultForAz as the filter name.

    • enable-dns64 - Indicates whether DNS queries made to the Amazon-provided DNS Resolver in this subnet should return synthetic IPv6 addresses for IPv4-only destinations.

    • enable-lni-at-device-index - 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).

    • ipv6-cidr-block-association.ipv6-cidr-block - An IPv6 CIDR block associated with the subnet.

    • ipv6-cidr-block-association.association-id - An association ID for an IPv6 CIDR block associated with the subnet.

    • ipv6-cidr-block-association.state - The state of an IPv6 CIDR block associated with the subnet.

    • ipv6-native - Indicates whether this is an IPv6 only subnet ( true | false).

    • map-customer-owned-ip-on-launch - Indicates whether a network interface created in this subnet (including a network interface created by RunInstances) receives a customer-owned IPv4 address.

    • map-public-ip-on-launch - Indicates whether instances launched in this subnet receive a public IPv4 address.

    • outpost-arn - The Amazon Resource Name (ARN) of the Outpost.

    • owner-id - The ID of the Amazon Web Services account that owns the subnet.

    • private-dns-name-options-on-launch.hostname-type - The type of hostname to assign to instances in the subnet at launch. For IPv4-only and dual-stack (IPv4 and IPv6) subnets, an instance DNS name can be based on the instance IPv4 address (ip-name) or the instance ID (resource-name). For IPv6 only subnets, an instance DNS name must be based on the instance ID (resource-name).

    • private-dns-name-options-on-launch.enable-resource-name-dns-a-record - Indicates whether to respond to DNS queries for instance hostnames with DNS A records.

    • private-dns-name-options-on-launch.enable-resource-name-dns-aaaa-record - Indicates whether to respond to DNS queries for instance hostnames with DNS AAAA records.

    • state - The state of the subnet ( pending | available).

    • subnet-arn - The Amazon Resource Name (ARN) of the subnet.

    • subnet-id - The ID of the subnet.

    • tag - The key/value combination of a tag assigned to the resource. Use the tag key in the filter name and the tag value as the filter value. For example, to find all resources that have a tag with the key Owner and the value TeamA, specify tag:Owner for the filter name and TeamA for the filter value.

    • tag-key - The key of a tag assigned to the resource. Use this filter to find all resources assigned a tag with a specific key, regardless of the tag value.

    • vpc-id - The ID of the VPC for the subnet.

    • (dict) –

      A filter name and value pair that is used to return a more specific list of results from a describe operation. Filters can be used to match a set of resources by specific criteria, such as tags, attributes, or IDs.

      If you specify multiple filters, the filters are joined with an AND, and the request returns only results that match all of the specified filters.

      For more information, see List and filter using the CLI and API in the Amazon EC2 User Guide.

      • Name (string) –

        The name of the filter. Filter names are case-sensitive.

      • Values (list) –

        The filter values. Filter values are case-sensitive. If you specify multiple values for a filter, the values are joined with an OR, and the request returns all results that match any of the specified values.

        • (string) –

  • SubnetIds (list) –

    The IDs of the subnets.

    Default: Describes all your subnets.

    • (string) –

  • NextToken (string) – The token returned from a previous paginated request. Pagination continues from the end of the items returned by the previous request.

  • MaxResults (integer) – The maximum number of items to return for this request. To get the next page of items, make another request with the token returned in the output. For more information, see Pagination.

  • 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.

Return type:

dict

Returns:

Response Syntax

{
    'NextToken': 'string',
    'Subnets': [
        {
            'AvailabilityZoneId': 'string',
            'EnableLniAtDeviceIndex': 123,
            'MapCustomerOwnedIpOnLaunch': True|False,
            'CustomerOwnedIpv4Pool': 'string',
            'OwnerId': 'string',
            'AssignIpv6AddressOnCreation': True|False,
            'Ipv6CidrBlockAssociationSet': [
                {
                    'AssociationId': 'string',
                    'Ipv6CidrBlock': 'string',
                    'Ipv6CidrBlockState': {
                        'State': 'associating'|'associated'|'disassociating'|'disassociated'|'failing'|'failed',
                        'StatusMessage': 'string'
                    },
                    'Ipv6AddressAttribute': 'public'|'private',
                    'IpSource': 'amazon'|'byoip'|'none'
                },
            ],
            '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
            },
            'BlockPublicAccessStates': {
                'InternetGatewayBlockMode': 'off'|'block-bidirectional'|'block-ingress'
            },
            'SubnetId': 'string',
            'State': 'pending'|'available'|'unavailable',
            'VpcId': 'string',
            'CidrBlock': 'string',
            'AvailableIpAddressCount': 123,
            'AvailabilityZone': 'string',
            'DefaultForAz': True|False,
            'MapPublicIpOnLaunch': True|False
        },
    ]
}

Response Structure

  • (dict) –

    • NextToken (string) –

      The token to include in another request to get the next page of items. This value is null when there are no more items to return.

    • Subnets (list) –

      Information about the subnets.

      • (dict) –

        Describes a subnet.

        • AvailabilityZoneId (string) –

          The AZ ID of the subnet.

        • 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).

        • 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.

        • 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.

            • Ipv6AddressAttribute (string) –

              Public IPv6 addresses are those advertised on the internet from Amazon Web Services. Private IP addresses are not and cannot be advertised on the internet from Amazon Web Services.

            • IpSource (string) –

              The source that allocated the IP address space. byoip or amazon indicates public IP address space allocated by Amazon or space that you have allocated with Bring your own IP (BYOIP). none indicates private space.

        • 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.

        • BlockPublicAccessStates (dict) –

          The state of VPC Block Public Access (BPA).

          • InternetGatewayBlockMode (string) –

            The mode of VPC BPA.

            • off: VPC BPA is not enabled and traffic is allowed to and from internet gateways and egress-only internet gateways in this Region.

            • block-bidirectional: Block all traffic to and from internet gateways and egress-only internet gateways in this Region (except for excluded VPCs and subnets).

            • block-ingress: Block all internet traffic to the VPCs in this Region (except for VPCs or subnets which are excluded). Only traffic to and from NAT gateways and egress-only internet gateways is allowed because these gateways only allow outbound connections to be established.

        • SubnetId (string) –

          The ID of the subnet.

        • State (string) –

          The current state of the subnet.

        • VpcId (string) –

          The ID of the VPC the subnet is in.

        • CidrBlock (string) –

          The IPv4 CIDR block assigned to the subnet.

        • AvailableIpAddressCount (integer) –

          The number of unused private IPv4 addresses in the subnet. The IPv4 addresses for any stopped instances are considered unavailable.

        • AvailabilityZone (string) –

          The Availability Zone of the subnet.

        • DefaultForAz (boolean) –

          Indicates whether this is the default subnet for the Availability Zone.

        • MapPublicIpOnLaunch (boolean) –

          Indicates whether instances launched in this subnet receive a public IPv4 address.

          Amazon Web Services charges for all public IPv4 addresses, including public IPv4 addresses associated with running instances and Elastic IP addresses. For more information, see the Public IPv4 Address tab on the Amazon VPC pricing page.

Examples

This example describes the subnets for the specified VPC.

response = client.describe_subnets(
    Filters=[
        {
            'Name': 'vpc-id',
            'Values': [
                'vpc-a01106c2',
            ],
        },
    ],
)

print(response)

Expected Output:

{
    'Subnets': [
        {
            'AvailabilityZone': 'us-east-1c',
            'AvailableIpAddressCount': 251,
            'CidrBlock': '10.0.1.0/24',
            'DefaultForAz': False,
            'MapPublicIpOnLaunch': False,
            'State': 'available',
            'SubnetId': 'subnet-9d4a7b6c',
            'VpcId': 'vpc-a01106c2',
        },
    ],
    'ResponseMetadata': {
        '...': '...',
    },
}