Add a local network interface to an EC2 instance in an Outposts subnet - AWS Outposts
View the local network interfaceConfigure the operating system

Add a local network interface to an EC2 instance in an Outposts subnet

You can add a local network interface to an Amazon EC2 instance on an Outposts subnet during or after launch. You do so by adding a secondary network interface to the instance, using the device index that you specified when you enabled the Outpost subnet for local network interfaces.

Consideration

When you specify the secondary network interface using the console, the network interface is created using device index 1. If this is not the device index that you specified when you enabled the Outpost subnet for local network interfaces, you can specify the correct device index by using the AWS CLI or an AWS SDK instead. For example, use the following commands from the AWS CLI: create-network-interface and attach-network-interface.

Use the following procedure to add the local network interface after you launch the instance. For information about adding it during instance launch, see Launch an instance on the Outpost.

To add a local network interface to an EC2 instance

  1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

  2. In the navigation pane, choose Network and Security, Network Interfaces.

  3. Create the network interface

    1. Choose Create network interface.

    2. Select the same Outpost subnet as the instance.

    3. Verify that Private IPv4 address is set to Auto-assign.

    4. Select any security group. Security groups do not apply to local network interface, so the security group that you select is not relevant.

    5. Choose Create network interface.

  4. Attach the network interface to the instance

    1. Select the check box for the newly created network interface.

    2. Choose Actions, Attach.

    3. Choose the instance.

    4. Choose Attach. The network interface is attached at device index 1. If you specified 1 as the device index for the local network interface for the Outpost subnet, this network interface is the local network interface for the instance.

View the local network interface

While the instance is in the running state, you can use the Amazon EC2 console to view both the elastic network interface and the local network interface for the instances in your Outpost subnet. Select the instance and choose the Networking tab.

The console displays a private IPv4 address for the local network interface from the subnet CIDR. This address is not the IP address of the local network interface, and it is not usable. However, this address is allocated from the subnet CIDR, so you must account for it in your subnet sizing. You must set the IP address for the local network interface within the guest operating system, either statically or through your DHCP server.

Configure the operating system

After you enable local network interfaces, Amazon EC2 instances will have two network interfaces, one of which is a local network interface. Ensure that you configure the operating system of the Amazon EC2 instances that you launch to support a multi-homed networking configuration.