Work with prefixes - Amazon Elastic Compute Cloud
Assign prefixes during network interface creationAssign prefixes to existing network interfacesConfigure your operating system for network interfaces with prefixesView the prefixes assigned to your network interfacesRemove prefixes from your network interfaces
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Work with prefixes

You can use prefixes with your network interfaces as follows.

Assign prefixes during network interface creation

If you use the automatic assignment option, you can reserve a block of IP addresses in your subnet. Amazon chooses the prefixes from this block. For more information, see Subnet CIDR reservations in the Amazon VPC User Guide.

After you have created the network interface, use the attach-network-interface Amazon CLI command to attach the network interface to your instance. You must configure your operating system to work with network interfaces with prefixes. For more information, see Configure your operating system for network interfaces with prefixes.

Assign automatic prefixes during network interface creation

You can assign automatic prefixes during network interface creation using one of the following methods.

Console
To assign automatic prefixes during network interface creation

  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. In the navigation pane, choose Network Interfaces and then choose Create network interface.

  3. Specify a description for the network interface, select the subnet in which to create the network interface, and configure the private IPv4 and IPv6 addresses.

  4. Expand Advanced settings and do the following:

    1. To automatically assign an IPv4 prefix, for IPv4 prefix delegation, choose Auto-assign. Then for Number of IPv4 prefixes, specify the number of prefixes to assign.

    2. To automatically assign an IPv6 prefix, for IPv6 prefix delegation, choose Auto-assign. Then for Number of IPv6 prefixes, specify the number of prefixes to assign.

      Note

      IPv6 prefix delegation appears only if the selected subnet is enabled for IPv6.

  5. Select the security groups to associate with the network interface and assign resource tags if needed.

  6. Choose Create network interface.

Amazon CLI
To assign automatic IPv4 prefixes during network interface creation

Use the create-network-interface command and set --ipv4-prefix-count to the number of prefixes that you want Amazon to assign. In the following example, Amazon assigns 1 prefix.

$ aws ec2 create-network-interface \
--subnet-id subnet-047cfed18eEXAMPLE \
--description "IPv4 automatic example" \
--ipv4-prefix-count 1

Example output

{
    "NetworkInterface": {
        "AvailabilityZone": "us-west-2a",
        "Description": "IPv4 automatic example",
        "Groups": [
            {
                "GroupName": "default",
                "GroupId": "sg-044c2de2c4EXAMPLE"
            }
        ],
        "InterfaceType": "interface",
        "Ipv6Addresses": [],
        "MacAddress": "02:98:65:dd:18:47",
        "NetworkInterfaceId": "eni-02b80b4668EXAMPLE",
        "OwnerId": "123456789012",
        "PrivateIpAddress": "10.0.0.62",
        "PrivateIpAddresses": [
            {
                "Primary": true,
                "PrivateIpAddress": "10.0.0.62"
            }
        ],
        "Ipv4Prefixes": [
            {
                "Ipv4Prefix": "10.0.0.208/28"
            }
        ],
        "RequesterId": "AIDAIV5AJI5LXF5XXDPCO",
        "RequesterManaged": false,
        "SourceDestCheck": true,
        "Status": "pending",
        "SubnetId": "subnet-047cfed18eEXAMPLE",
        "TagSet": [],
        "VpcId": "vpc-0e12f52b21EXAMPLE"
    }
}
To assign automatic IPv6 prefixes during network interface creation

Use the create-network-interface command and set --ipv6-prefix-count to the number of prefixes that you want Amazon to assign. In the following example, Amazon assigns 1 prefix.

$ aws ec2 create-network-interface \
--subnet-id subnet-047cfed18eEXAMPLE \
--description "IPv6 automatic example" \
--ipv6-prefix-count 1

Example output

{
    "NetworkInterface": {
        "AvailabilityZone": "us-west-2a",
        "Description": "IPv6 automatic example",
        "Groups": [
            {
                "GroupName": "default",
                "GroupId": "sg-044c2de2c4EXAMPLE"
            }
        ],
        "InterfaceType": "interface",
        "Ipv6Addresses": [],
        "MacAddress": "02:bb:e4:31:fe:09",
        "NetworkInterfaceId": "eni-006edbcfa4EXAMPLE",
        "OwnerId": "123456789012",
        "PrivateIpAddress": "10.0.0.73",
        "PrivateIpAddresses": [
            {
                "Primary": true,
                "PrivateIpAddress": "10.0.0.73"
            }
        ],
        "Ipv6Prefixes": [
            {
                "Ipv6Prefix": "2600:1f13:fc2:a700:1768::/80"
            }
        ],
        "RequesterId": "AIDAIV5AJI5LXF5XXDPCO",
        "RequesterManaged": false,
        "SourceDestCheck": true,
        "Status": "pending",
        "SubnetId": "subnet-047cfed18eEXAMPLE",
        "TagSet": [],
        "VpcId": "vpc-0e12f52b21EXAMPLE"
    }
}

Assign specific prefixes during network interface creation

You can assign specific prefixes during network interface creation using one of the following methods.

Console
To assign specific prefixes during network interface creation

  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. In the navigation pane, choose Network Interfaces and then choose Create network interface.

  3. Specify a description for the network interface, select the subnet in which to create the network interface, and configure the private IPv4 and IPv6 addresses.

  4. Expand Advanced settings and do the following:

    1. To assign a specific IPv4 prefix, for IPv4 prefix delegation, choose Custom. Then choose Add new prefix and enter the prefix to use.

    2. To assign a specific IPv6 prefix, for IPv6 prefix delegation, choose Custom. Then choose Add new prefix and enter the prefix to use.

      Note

      IPv6 prefix delegation appears only if the selected subnet is enabled for IPv6.

  5. Select the security groups to associate with the network interface and assign resource tags if needed.

  6. Choose Create network interface.

Amazon CLI
To assign specific IPv4 prefixes during network interface creation

Use the create-network-interface command and set --ipv4-prefixes to the prefixes. Amazon selects IP addresses from this range. In the following example, the prefix CIDR is 10.0.0.208/28.

$ aws ec2 create-network-interface \
    --subnet-id subnet-047cfed18eEXAMPLE \
    --description "IPv4 manual example" \
    --ipv4-prefixes Ipv4Prefix=10.0.0.208/28

Example output

{
        "NetworkInterface": {
            "AvailabilityZone": "us-west-2a",
            "Description": "IPv4 manual example",
            "Groups": [
                {
                    "GroupName": "default",
                    "GroupId": "sg-044c2de2c4EXAMPLE"
                }
            ],
            "InterfaceType": "interface",
            "Ipv6Addresses": [],
            "MacAddress": "02:98:65:dd:18:47",
            "NetworkInterfaceId": "eni-02b80b4668EXAMPLE",
            "OwnerId": "123456789012",
            "PrivateIpAddress": "10.0.0.62",
            "PrivateIpAddresses": [
                {
                    "Primary": true,
                    "PrivateIpAddress": "10.0.0.62"
                }
            ],
            "Ipv4Prefixes": [
                {
                    "Ipv4Prefix": "10.0.0.208/28"
                }
            ],
            "RequesterId": "AIDAIV5AJI5LXF5XXDPCO",
            "RequesterManaged": false,
            "SourceDestCheck": true,
            "Status": "pending",
            "SubnetId": "subnet-047cfed18eEXAMPLE",
            "TagSet": [],
            "VpcId": "vpc-0e12f52b21EXAMPLE"
        }
    }
To assign specific IPv6 prefixes during network interface creation

Use the create-network-interface command and set --ipv6-prefixes to the prefixes. Amazon selects IP addresses from this range. In the following example, the prefix CIDR is 2600:1f13:fc2:a700:1768::/80.

$ aws ec2 create-network-interface \
    --subnet-id subnet-047cfed18eEXAMPLE \
    --description "IPv6 manual example" \
    --ipv6-prefixes Ipv6Prefix=2600:1f13:fc2:a700:1768::/80

Example output

{
        "NetworkInterface": {
            "AvailabilityZone": "us-west-2a",
            "Description": "IPv6 automatic example",
            "Groups": [
                {
                    "GroupName": "default",
                    "GroupId": "sg-044c2de2c4EXAMPLE"
                }
            ],
            "InterfaceType": "interface",
            "Ipv6Addresses": [],
            "MacAddress": "02:bb:e4:31:fe:09",
            "NetworkInterfaceId": "eni-006edbcfa4EXAMPLE",
            "OwnerId": "123456789012",
            "PrivateIpAddress": "10.0.0.73",
            "PrivateIpAddresses": [
                {
                    "Primary": true,
                    "PrivateIpAddress": "10.0.0.73"
                }
            ],
            "Ipv6Prefixes": [
                {
                    "Ipv6Prefix": "2600:1f13:fc2:a700:1768::/80"
                }
            ],
            "RequesterId": "AIDAIV5AJI5LXF5XXDPCO",
            "RequesterManaged": false,
            "SourceDestCheck": true,
            "Status": "pending",
            "SubnetId": "subnet-047cfed18eEXAMPLE",
            "TagSet": [],
            "VpcId": "vpc-0e12f52b21EXAMPLE"
        }
    }

Assign prefixes to existing network interfaces

After you have assigned the prefixes, use the attach-network-interface Amazon CLI command to attach the network interface to your instance. You must configure your operating system to work with network interfaces with prefixes. For more information, see Configure your operating system for network interfaces with prefixes.

Assign automatic prefixes to an existing network interface

You can assign automatic prefixes to an existing network interface using one of the following methods.

Console
To assign automatic prefixes to an existing network interface

  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. In the navigation pane, choose Network Interfaces.

  3. Select the network interface to which to assign the prefixes, and choose Actions, Manage prefixes.

  4. To automatically assign an IPv4 prefix, for IPv4 prefix delegation, choose Auto-assign. Then for Number of IPv4 prefixes, specify the number of prefixes to assign.

  5. To automatically assign an IPv6 prefix, for IPv6 prefix delegation, choose Auto-assign. Then for Number of IPv6 prefixes, specify the number of prefixes to assign.

    Note

    IPv6 prefix delegation appears only if the selected subnet is enabled for IPv6.

  6. Choose Save.

Amazon CLI

You can use the assign-ipv6-addresses command to assign IPv6 prefixes and the assign-private-ip-addresses command to assign IPv4 prefixes to existing network interfaces.

To assign automatic IPv4 prefixes to an existing network interface

Use the assign-private-ip-addresses command and set --ipv4-prefix-count to the number of prefixes that you want Amazon to assign. In the following example, Amazon assigns 1 IPv4 prefix.

$ aws ec2 assign-private-ip-addresses \
--network-interface-id eni-081fbb4095EXAMPLE \
--ipv4-prefix-count 1

Example output

{
    "NetworkInterfaceId": "eni-081fbb4095EXAMPLE",
    "AssignedIpv4Prefixes": [
        {
            "Ipv4Prefix": "10.0.0.176/28"
        }
    ]
}
To assign automatic IPv6 prefixes to an existing network interface

Use the assign-ipv6-addresses command and set --ipv6-prefix-count to the number of prefixes that you want Amazon to assign. In the following example, Amazon assigns 1 IPv6 prefix.

$ aws ec2 assign-ipv6-addresses \
--network-interface-id eni-00d577338cEXAMPLE \
--ipv6-prefix-count 1

Example output

{
    "AssignedIpv6Prefixes": [
        "2600:1f13:fc2:a700:18bb::/80"
    ],
    "NetworkInterfaceId": "eni-00d577338cEXAMPLE"
}

Assign specific prefixes to an existing network interface

You can assign specific prefixes to an existing network interface using one of the following methods.

Console
To assign specific prefixes to an existing network interface

  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. In the navigation pane, choose Network Interfaces.

  3. Select the network interface to which to assign the prefixes, and choose Actions, Manage prefixes.

  4. To assign a specific IPv4 prefix, for IPv4 prefix delegation, choose Custom. Then choose Add new prefix and enter the prefix to use.

  5. To assign a specific IPv6 prefix, for IPv6 prefix delegation, choose Custom. Then choose Add new prefix and enter the prefix to use.

    Note

    IPv6 prefix delegation appears only if the selected subnet is enabled for IPv6.

  6. Choose Save.

Amazon CLI
Assign specific IPv4 prefixes to an existing network interface

Use the assign-private-ip-addresses command and set --ipv4-prefixes to the prefix. Amazon selects IPv4 addresses from this range. In the following example, the prefix CIDR is 10.0.0.208/28.

$ aws ec2 assign-private-ip-addresses \
--network-interface-id eni-081fbb4095EXAMPLE \
--ipv4-prefixes 10.0.0.208/28

Example output

{
    "NetworkInterfaceId": "eni-081fbb4095EXAMPLE",
    "AssignedIpv4Prefixes": [
        {
            "Ipv4Prefix": "10.0.0.208/28"
        }
    ]
}
Assign specific IPv6 prefixes to an existing network interface

Use the assign-ipv6-addresses command and set --ipv6-prefixes to the prefix. Amazon selects IPv6 addresses from this range. In the following example, the prefix CIDR is 2600:1f13:fc2:a700:18bb::/80.

$ aws ec2 assign-ipv6-addresses \
--network-interface-id eni-00d577338cEXAMPLE \
--ipv6-prefixes 2600:1f13:fc2:a700:18bb::/80

Example output

{
    "NetworkInterfaceId": "eni-00d577338cEXAMPLE",
    "AssignedIpv6Prefixes": [
        {
            "Ipv6Prefix": "2600:1f13:fc2:a700:18bb::/80"
        }
    ]
}

Configure your operating system for network interfaces with prefixes

Amazon Linux AMIs might contain additional scripts installed by Amazon, known as ec2-net-utils. These scripts optionally automate the configuration of your network interfaces. They are available for Amazon Linux only.

If you are not using Amazon Linux, you can use a Container Network Interface (CNI) for Kubernetes plug-in, or dockerd if you use Docker to manage your containers.

View the prefixes assigned to your network interfaces

You can view the prefixes assigned to your network interfaces using one of the following methods.

Console
To view the automatic prefixes assigned to an existing network interface

  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. In the navigation pane, choose Network Interfaces.

  3. Select the network interface for which to view the prefixes and choose the Details tab.

  4. The IPv4 Prefix Delegation field lists the assigned IPv4 prefixes, and the IPv6 Prefix Delegation field lists the assigned IPv6 prefixes.

Amazon CLI

You can use the describe-network-interfaces Amazon CLI command to view the prefixes assigned to your network interfaces.

$ aws ec2 describe-network-interfaces

Example output

{
    "NetworkInterfaces": [
        {
            "AvailabilityZone": "us-west-2a",
            "Description": "IPv4 automatic example",
            "Groups": [
                {
                    "GroupName": "default",
                    "GroupId": "sg-044c2de2c4EXAMPLE"
                }
            ],
            "InterfaceType": "interface",
            "Ipv6Addresses": [],
            "MacAddress": "02:98:65:dd:18:47",
            "NetworkInterfaceId": "eni-02b80b4668EXAMPLE",
            "OwnerId": "123456789012",
            "PrivateIpAddress": "10.0.0.62",
            "PrivateIpAddresses": [
                {
                    "Primary": true,
                    "PrivateIpAddress": "10.0.0.62"
                }
            ],
            "Ipv4Prefixes": [
                {
                    "Ipv4Prefix": "10.0.0.208/28"
                }
            ],
            "Ipv6Prefixes": [],
            "RequesterId": "AIDAIV5AJI5LXF5XXDPCO",
            "RequesterManaged": false,
            "SourceDestCheck": true,
            "Status": "available",
            "SubnetId": "subnet-05eef9fb78EXAMPLE",
            "TagSet": [],
            "VpcId": "vpc-0e12f52b2146bf252"
        },
        {
            "AvailabilityZone": "us-west-2a",
            "Description": "IPv6 automatic example",
            "Groups": [
                {
                    "GroupName": "default",
                    "GroupId": "sg-044c2de2c411c91b5"
                }
            ],
            "InterfaceType": "interface",
            "Ipv6Addresses": [],
            "MacAddress": "02:bb:e4:31:fe:09",
            "NetworkInterfaceId": "eni-006edbcfa4EXAMPLE",
            "OwnerId": "123456789012",
            "PrivateIpAddress": "10.0.0.73",
            "PrivateIpAddresses": [
                {
                    "Primary": true,
                    "PrivateIpAddress": "10.0.0.73"
                }
            ],
            "Ipv4Prefixes": [],
            "Ipv6Prefixes": [
                {
                    "Ipv6Prefix": "2600:1f13:fc2:a700:1768::/80"
                }
            ],
            "RequesterId": "AIDAIV5AJI5LXF5XXDPCO",
            "RequesterManaged": false,
            "SourceDestCheck": true,
            "Status": "available",
            "SubnetId": "subnet-05eef9fb78EXAMPLE",
            "TagSet": [],
            "VpcId": "vpc-0e12f52b21EXAMPLE"
        }
    ]
}

Remove prefixes from your network interfaces

You can remove prefixes from your network interfaces using one of the following methods.

Console
To remove the prefixes from a network interface

  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. In the navigation pane, choose Network Interfaces.

  3. Select the network interface from which to remove the prefixes and choose Actions, Manage prefixes.

  4. Do one of the following:

    • To remove all assigned prefixes, for IPv4 prefix delegation and IPv6 prefix delegation, choose Do not assign.

    • To remove specific assigned prefixes, for IPv4 prefix delegation or IPv6 prefix delegation, choose Custom and then choose Unassign next to the prefixes to remove.

    Note

    IPv6 prefix delegation appears only if the selected subnet is enabled for IPv6.

  5. Choose Save.

Amazon CLI

You can use the unassign-ipv6-addresses command to remove IPv6 prefixes and the unassign-private-ip-addresses commands to remove IPv4 prefixes from your existing network interfaces.

To remove IPv4 prefixes from a network interface

Use the unassign-private-ip-addresses command and set --ipv4-prefix to the address that you want to remove.

$ aws ec2 unassign-private-ip-addresses \
--network-interface-id eni-081fbb4095EXAMPLE \
--ipv4-prefixes 10.0.0.176/28
To remove IPv6 prefixes from a network interface

Use the unassign-ipv6-addresses command and set --ipv6-prefix to the address that you want to remove.

$ aws ec2 unassign-ipv6-addresses \
--network-interface-id eni-00d577338cEXAMPLE \
--ipv6-prefix 2600:1f13:fc2:a700:18bb::/80