Use AllocateAddress with an Amazon SDK or CLI

    /// <summary>
    /// Allocates an Elastic IP address that can be associated with an Amazon EC2
    // instance. By using an Elastic IP address, you can keep the public IP address
    // constant even when you restart the associated instance.
    /// </summary>
    /// <returns>The response object for the allocated address.</returns>
    public async Task<AllocateAddressResponse> AllocateAddress()
    {
        var request = new AllocateAddressRequest();

        try
        {
            var response = await _amazonEC2.AllocateAddressAsync(request);
            Console.WriteLine($"Allocated IP: {response.PublicIp} with allocation ID {response.AllocationId}.");
            return response;
        }
        catch (AmazonEC2Exception ec2Exception)
        {
            if (ec2Exception.ErrorCode == "AddressLimitExceeded")
            {
                // For more information on Elastic IP address quotas, see:
                // https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/elastic-ip-addresses-eip.html#using-instance-addressing-limit
                _logger.LogError($"Unable to allocate Elastic IP, address limit exceeded. {ec2Exception.Message}");
            }

            throw;
        }
        catch (Exception ex)
        {
            _logger.LogError($"An error occurred while allocating Elastic IP.: {ex.Message}");
            throw;
        }
    }

###############################################################################
# function ec2_allocate_address
#
# This function allocates an Elastic IP address for use with Amazon Elastic Compute Cloud (Amazon EC2) instances in a specific AWS Region.
#
# Parameters:
#       -d domain - The domain for the Elastic IP address (either 'vpc' or 'standard').
#
# Returns:
#       The allocated Elastic IP address, or an error message if the operation fails.
# And:
#       0 - If successful.
#       1 - If it fails.
#
###############################################################################
function ec2_allocate_address() {
  local domain response

  # Function to display usage information
  function usage() {
    echo "function ec2_allocate_address"
    echo "Allocates an Elastic IP address for use with Amazon Elastic Compute Cloud (Amazon EC2) instances in a specific AWS Region."
    echo "  -d domain - The domain for the Elastic IP address (either 'vpc' or 'standard')."
    echo ""
  }

  # Parse the command-line arguments
  while getopts "d:h" option; do
    case "${option}" in
      d) domain="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  # Validate the input parameters
  if [[ -z "$domain" ]]; then
    errecho "ERROR: You must provide a domain with the -d parameter (either 'vpc' or 'standard')."
    return 1
  fi

  if [[ "$domain" != "vpc" && "$domain" != "standard" ]]; then
    errecho "ERROR: Invalid domain value. Must be either 'vpc' or 'standard'."
    return 1
  fi

  # Allocate the Elastic IP address
  response=$(aws ec2 allocate-address \
    --domain "$domain" \
    --query "[PublicIp,AllocationId]" \
    --output text) || {
    aws_cli_error_log ${?}
    errecho "ERROR: AWS reports allocate-address operation failed."
    errecho "$response"
    return 1
  }

  echo "$response"
  return 0
}

The utility functions used in this example.

###############################################################################
# function errecho
#
# This function outputs everything sent to it to STDERR (standard error output).
###############################################################################
function errecho() {
  printf "%s\n" "$*" 1>&2
}

##############################################################################
# function aws_cli_error_log()
#
# This function is used to log the error messages from the AWS CLI.
#
# The function expects the following argument:
#         $1 - The error code returned by the AWS CLI.
#
#  Returns:
#          0: - Success.
#
##############################################################################
function aws_cli_error_log() {
  local err_code=$1
  errecho "Error code : $err_code"
  if [ "$err_code" == 1 ]; then
    errecho "  One or more S3 transfers failed."
  elif [ "$err_code" == 2 ]; then
    errecho "  Command line failed to parse."
  elif [ "$err_code" == 130 ]; then
    errecho "  Process received SIGINT."
  elif [ "$err_code" == 252 ]; then
    errecho "  Command syntax invalid."
  elif [ "$err_code" == 253 ]; then
    errecho "  The system environment or configuration was invalid."
  elif [ "$err_code" == 254 ]; then
    errecho "  The service returned an error."
  elif [ "$err_code" == 255 ]; then
    errecho "  255 is a catch-all error."
  fi

  return 0
}

//! Allocate an Elastic IP address and associate it with an Amazon Elastic Compute Cloud
//! (Amazon EC2) instance.
/*!
  \param instanceID: An EC2 instance ID.
  \param[out] publicIPAddress: String to return the public IP address.
  \param[out] allocationID: String to return the allocation ID.
  \param clientConfiguration: AWS client configuration.
  \return bool: Function succeeded.
 */
bool AwsDoc::EC2::allocateAndAssociateAddress(const Aws::String &instanceId, Aws::String &publicIPAddress,
                                              Aws::String &allocationID,
                                              const Aws::Client::ClientConfiguration &clientConfiguration) {
    Aws::EC2::EC2Client ec2Client(clientConfiguration);

    Aws::EC2::Model::AllocateAddressRequest request;
    request.SetDomain(Aws::EC2::Model::DomainType::vpc);

    const Aws::EC2::Model::AllocateAddressOutcome outcome =
            ec2Client.AllocateAddress(request);
    if (!outcome.IsSuccess()) {
        std::cerr << "Failed to allocate Elastic IP address:" <<
                  outcome.GetError().GetMessage() << std::endl;
        return false;
    }
    const Aws::EC2::Model::AllocateAddressResponse &response = outcome.GetResult();
    allocationID = response.GetAllocationId();
    publicIPAddress = response.GetPublicIp();


    return true;
}

Example 1: To allocate an Elastic IP address from Amazon's address pool

The following allocate-address example allocates an Elastic IP address. Amazon EC2 selects the address from Amazon's address pool.

aws ec2 allocate-address

Output:

{
    "PublicIp": "70.224.234.241",
    "AllocationId": "eipalloc-01435ba59eEXAMPLE",
    "PublicIpv4Pool": "amazon",
    "NetworkBorderGroup": "us-west-2",
    "Domain": "vpc"
}

For more information, see Elastic IP addresses in the Amazon EC2 User Guide.

Example 2: To allocate an Elastic IP address and associate it with a network border group

The following allocate-address example allocates an Elastic IP address and associates it with the specified network border group.

aws ec2 allocate-address \
    --network-border-group us-west-2-lax-1

Output:

{
    "PublicIp": "70.224.234.241",
    "AllocationId": "eipalloc-e03dd489ceEXAMPLE",
    "PublicIpv4Pool": "amazon",
    "NetworkBorderGroup": "us-west-2-lax-1",
    "Domain": "vpc"
}

For more information, see Elastic IP addresses in the Amazon EC2 User Guide.

Example 3: To allocate an Elastic IP address from an address pool that you own

The following allocate-address example allocates an Elastic IP address from an address pool that you have brought to your Amazon Web Services account. Amazon EC2 selects the address from the address pool.

aws ec2 allocate-address \
    --public-ipv4-pool ipv4pool-ec2-1234567890abcdef0

Output:

{
    "AllocationId": "eipalloc-02463d08ceEXAMPLE",
    "NetworkBorderGroup": "us-west-2",
    "CustomerOwnedIp": "18.218.95.81",
    "CustomerOwnedIpv4Pool": "ipv4pool-ec2-1234567890abcdef0",
    "Domain": "vpc"
    "NetworkBorderGroup": "us-west-2",
}

For more information, see Elastic IP addresses in the Amazon EC2 User Guide.

    /**
     * Allocates an Elastic IP address asynchronously in the VPC domain.
     *
     * @return a {@link CompletableFuture} containing the allocation ID of the allocated Elastic IP address
     */
    public CompletableFuture<String> allocateAddressAsync() {
        AllocateAddressRequest allocateRequest = AllocateAddressRequest.builder()
            .domain(DomainType.VPC)
            .build();

        CompletableFuture<AllocateAddressResponse> responseFuture = getAsyncClient().allocateAddress(allocateRequest);
        return responseFuture.thenApply(AllocateAddressResponse::allocationId).whenComplete((result, ex) -> {
            if (ex != null) {
                throw new RuntimeException("Failed to allocate address", ex);
            }
        });
    }

import { AllocateAddressCommand, EC2Client } from "@aws-sdk/client-ec2";

/**
 * Allocates an Elastic IP address to your AWS account.
 */
export const main = async () => {
  const client = new EC2Client({});
  const command = new AllocateAddressCommand({});

  try {
    const { AllocationId, PublicIp } = await client.send(command);
    console.log("A new IP address has been allocated to your account:");
    console.log(`ID: ${AllocationId} Public IP: ${PublicIp}`);
    console.log(
      "You can view your IP addresses in the AWS Management Console for Amazon EC2. Look under Network & Security > Elastic IPs",
    );
  } catch (caught) {
    if (caught instanceof Error && caught.name === "MissingParameter") {
      console.warn(`${caught.message}. Did you provide these values?`);
    } else {
      throw caught;
    }
  }
};
import { fileURLToPath } from "node:url";
// Call function if run directly.
if (process.argv[1] === fileURLToPath(import.meta.url)) {
  main();
}

suspend fun getAllocateAddress(instanceIdVal: String?): String? {
    val allocateRequest =
        AllocateAddressRequest {
            domain = DomainType.Vpc
        }

    Ec2Client { region = "us-west-2" }.use { ec2 ->
        val allocateResponse = ec2.allocateAddress(allocateRequest)
        val allocationIdVal = allocateResponse.allocationId

        val request =
            AssociateAddressRequest {
                instanceId = instanceIdVal
                allocationId = allocationIdVal
            }

        val associateResponse = ec2.associateAddress(request)
        return associateResponse.associationId
    }
}

Example 1: This example allocates an Elastic IP address to use with an instance in a VPC.

New-EC2Address -Domain Vpc

Output:

AllocationId         Domain      PublicIp
------------         ------      --------
eipalloc-12345678    vpc         198.51.100.2

Example 2: This example allocates an Elastic IP address to use with an instance in EC2-Classic.

New-EC2Address

Output:

AllocationId         Domain      PublicIp
------------         ------      --------
                     standard    203.0.113.17

class ElasticIpWrapper:
    """Encapsulates Amazon Elastic Compute Cloud (Amazon EC2) Elastic IP address actions using the client interface."""

    class ElasticIp:
        """Represents an Elastic IP and its associated instance."""

        def __init__(
            self, allocation_id: str, public_ip: str, instance_id: Optional[str] = None
        ) -> None:
            """
            Initializes the ElasticIp object.

            :param allocation_id: The allocation ID of the Elastic IP.
            :param public_ip: The public IP address of the Elastic IP.
            :param instance_id: The ID of the associated EC2 instance, if any.
            """
            self.allocation_id = allocation_id
            self.public_ip = public_ip
            self.instance_id = instance_id

    def __init__(self, ec2_client: Any) -> None:
        """
        Initializes the ElasticIpWrapper with an EC2 client.

        :param ec2_client: A Boto3 Amazon EC2 client. This client provides low-level
                           access to AWS EC2 services.
        """
        self.ec2_client = ec2_client
        self.elastic_ips: List[ElasticIpWrapper.ElasticIp] = []

    @classmethod
    def from_client(cls) -> "ElasticIpWrapper":
        """
        Creates an ElasticIpWrapper instance with a default EC2 client.

        :return: An instance of ElasticIpWrapper initialized with the default EC2 client.
        """
        ec2_client = boto3.client("ec2")
        return cls(ec2_client)


    def allocate(self) -> "ElasticIpWrapper.ElasticIp":
        """
        Allocates an Elastic IP address that can be associated with an Amazon EC2
        instance. By using an Elastic IP address, you can keep the public IP address
        constant even when you restart the associated instance.

        :return: The ElasticIp object for the newly created Elastic IP address.
        :raises ClientError: If the allocation fails, such as reaching the maximum limit of Elastic IPs.
        """
        try:
            response = self.ec2_client.allocate_address(Domain="vpc")
            elastic_ip = self.ElasticIp(
                allocation_id=response["AllocationId"], public_ip=response["PublicIp"]
            )
            self.elastic_ips.append(elastic_ip)
        except ClientError as err:
            if err.response["Error"]["Code"] == "AddressLimitExceeded":
                logger.error(
                    "Max IP's reached. Release unused addresses or contact AWS Support for an increase."
                )
            raise err
        return elastic_ip

# Creates an Elastic IP address in Amazon Virtual Private Cloud (Amazon VPC).
#
# @param ec2_client [Aws::EC2::Client] An initialized EC2 client.
# @return [String] The allocation ID corresponding to the Elastic IP address.
# @example
#   puts allocate_elastic_ip_address(Aws::EC2::Client.new(region: 'us-west-2'))
def allocate_elastic_ip_address(ec2_client)
  response = ec2_client.allocate_address(domain: 'vpc')
  response.allocation_id
rescue StandardError => e
  puts "Error allocating Elastic IP address: #{e.message}"
  'Error'
end

    pub async fn allocate_ip_address(&self) -> Result<AllocateAddressOutput, EC2Error> {
        self.client
            .allocate_address()
            .domain(DomainType::Vpc)
            .send()
            .await
            .map_err(EC2Error::from)
    }

    TRY.
        oo_result = lo_ec2->allocateaddress( iv_domain = 'vpc' ).   " oo_result is returned for testing purposes. "
        MESSAGE 'Allocated an Elastic IP address.' TYPE 'I'.
      CATCH /aws1/cx_rt_service_generic INTO DATA(lo_exception).
        DATA(lv_error) = |"{ lo_exception->av_err_code }" - { lo_exception->av_err_msg }|.
        MESSAGE lv_error TYPE 'E'.
    ENDTRY.