Avoiding Charges for Disassociated Elastic IP Address

Answer - A and C.

The AWS documentation mentions the following.

A disassociated Elastic IP address remains allocated to your account until you explicitly release it.

To ensure efficient use of Elastic IP addresses, we impose a small hourly charge if an Elastic IP address is not associated with a running instance, or if it is associated with a stopped instance or an unattached network interface.

While your instance is running, you are not charged for one Elastic IP address associated with the instance, but you are charged for any additional Elastic IP addresses associated with the instance.

For more information on Elastic IP's , one can visit the below URL:

If you disassociate an Elastic IP address from an instance, you will still be charged until you either release the Elastic IP address or associate it with a running instance or an unattached network interface. Here are the options you can choose to ensure that you don't get charged for the Elastic IP address:

A. Explicitly release the Elastic IP from your account: Releasing an Elastic IP address from your account will remove the Elastic IP address from your account and you will no longer be charged for it. To release an Elastic IP address, follow these steps:

1. Open the Amazon EC2 console.
2. In the navigation pane, choose "Elastic IPs".
3. Select the Elastic IP address that you want to release, and choose "Actions", "Release addresses".
4. In the confirmation dialog box, choose "Release".

B. Quickly associate it with any stopped instance: If you associate the Elastic IP address with a stopped instance, you will not be charged for the Elastic IP address until the instance is started. To associate an Elastic IP address with a stopped instance, follow these steps:

1. Open the Amazon EC2 console.
2. In the navigation pane, choose "Elastic IPs".
3. Select the Elastic IP address that you want to associate, and choose "Actions", "Associate IP address".
4. In the "Associate Elastic IP address" dialog box, select the stopped instance that you want to associate with the Elastic IP address, and choose "Associate".

C. Quickly associate it with any running instance: If you associate the Elastic IP address with a running instance, you will not be charged for the Elastic IP address. To associate an Elastic IP address with a running instance, follow these steps:

1. Open the Amazon EC2 console.
2. In the navigation pane, choose "Elastic IPs".
3. Select the Elastic IP address that you want to associate, and choose "Actions", "Associate IP address".
4. In the "Associate Elastic IP address" dialog box, select the running instance that you want to associate with the Elastic IP address, and choose "Associate".

D. Associate it with an unattached network interface: If you associate the Elastic IP address with an unattached network interface, you will not be charged for the Elastic IP address. To associate an Elastic IP address with an unattached network interface, follow these steps:

1. Open the Amazon EC2 console.
2. In the navigation pane, choose "Elastic IPs".
3. Select the Elastic IP address that you want to associate, and choose "Actions", "Associate IP address".
4. In the "Associate Elastic IP address" dialog box, select "Network interface" for the "Associate with" option.
5. In the "Network interface ID" box, enter the ID of the unattached network interface that you want to associate with the Elastic IP address.
6. Choose "Associate".