The instructions below describe what to do when you are travelling and won't have access to your number for 2FA:
If you are travelling soon and will not have access to your cellphone number for push notifications, you will not need a bypass code.
You can Please do the following before you leave:
Enroll your mobile device as a tablet. If you have internet access on your mobile device, you’ll still be able to authenticate.
Add a YubiKey token to your Duo account
Add the international number you’ll be using to your Duo account (instructions)
Create a ticket if you are going to an OFAC restricted country
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