Managing Two-Factor Authentication
Enabling two-factor user authentication (2FA) on your TeamCity server grants it an extra level of security. Users will have to verify their identity in two steps: by providing their regular credentials plus by submitting disposable keys, generated on their personal mobile devices.
2FA is set to Optional by default, but system administrators can make it Disabled or Mandatory on your server — in Administration | Authentication. The optional mode allows users to decide whether they want to enable 2FA for their accounts or not. The mandatory mode prevents users from accessing TeamCity without the 2FA verification.
After you enable the mandatory mode, users will have a grace period of 1 week during which they are supposed to set up 2FA for their accounts. New users will also get 1 week of no-2FA admission since the moment of their registration.
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