AWS add multiple MFA devices

Adding multiple MFA devices to AWS user account

I wanted to use more than one device for MFA. Well, once I was abroad and my phone broke for some time. My phone had MFA setup for the AWS account. Then I was locked out and couldn't log in to AWS without having the phone. This made me wanted to keep more than one MFA device.

However, AWS doesn't really allow you to add more than one device. It is to note that we always use virtual MFA devices and that is also the trick to do this. I haven't tried this with hardware devices though.

Just to be clear a virtual MFA allows us to set up an MFA application such as Google Authenticator or Microsoft Authenticator etc.

The Workaround

The trick is to use the same QR code to add another device. Also, this can be done using the secret too.

When the first device is added, keep the QR code (maybe take a screenshot and then add another MFA device.

Scan the same QR code with the next device or enter the secret key. The same pin numbers will be generated sequentially.

This is just because of how MFA works. I'll write another post about how it works later :)

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