Perform the following to enable MFA:
1. Sign in to the AWS Management Console and open the IAM console at https://console.aws.amazon.com/iam/.

2. In the navigation pane, choose Users.

3. In the User Name list, choose the name of the intended MFA user.

4. Choose the Security Credentials tab, and then choose Manage MFA Device.

5. In the Manage MFA Device wizard, choose A virtual MFA device, and then choose Next Step.

IAM generates and displays configuration information for the virtual MFA device, including a QR code graphic. The graphic is a representation of the ‘secret configuration key’ that is available for manual entry on devices that do not support QR codes.

6. Open your virtual MFA application. (For a list of apps that you can use for hosting virtual MFA devices, see Virtual MFA Applications.) If the virtual MFA application supports multiple accounts (multiple virtual MFA devices), choose the option to create a new account (a new virtual MFA device).

7. Determine whether the MFA app supports QR codes, and then do one of the following:

• Use the app to scan the QR code. For example, you might choose the camera icon or choose an option similar to Scan code, and then use the device’s camera to scan the code.
• In the Manage MFA Device wizard, choose Show secret key for manual configuration, and then type the secret configuration key into your MFA application. When you are finished, the virtual MFA device starts generating one-time passwords.

8. In the Manage MFA Device wizard, in the Authentication Code 1 box, type the one- time password that currently appears in the virtual MFA device. Wait up to 30 seconds for the device to generate a new one-time password. Then type the second one-time password into the Authentication Code 2 box. Choose Active Virtual MFA.

Forced IAM User Self-Service Remediation Amazon has published a pattern that forces users to self-service setup MFA before they have access to their complete permissions set. Until they complete this step, they cannot access their full permissions. This pattern can be used on new AWS accounts. It can also be used on existing accounts – it is recommended users are given instructions and a grace period to accomplish MFA enrollment before active enforcement on existing AWS accounts.

How to Delegate Management of Multi-Factor Authentication to AWS IAM Users

References:

1. http://tools.ietf.org/html/rfc6238
2. http://docs.aws.amazon.com/IAM/latest/UserGuide/id_credentials_mfa.html