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Step	Details
Locate your network interface in the interface list and right-click on it.	The right-click opens the context menu. Select Attach. This will open the window to enter the necessary information.
Select your instance and confirm entry.	Select your instance from the drop-down list and click on Attach. The state of your interface will change from available to in-use.
Verify that instance has second interface.	Select your instance in the instance list. The description tab in instance details should now display two network interfaces as shown in the example below:

 You can also attach/detach existing interfaces from the instance overview screen. Select your instance and then Actions > Networking > Attach or Detach network interface.

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An Elastic IP address is a static, public IPv4 address to be used for one of your network interfaces or instances. You can associate an Elastic IP address with any instance or network interface in your account.

 The advantage of associating the Elastic IP address with the network interface instead of directly with the instance is that you can move the network interface with its attributes easily from one instance to another.

 The initial automatically assigned public IP address will be removed as soon as you restart the network or the instance after adding a network interface with an Elastic IP address to your instance. Do not restart your network or your instance before you are sure you can reach it via the Elastic IP address. The automatically assigned public IP address will also be disabled if you assign an Elastic IP address to the primary Ethernet interface of the instance.

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