Can multifactor authentication be configured from multiple devices in ArcGIS Online and Portal for ArcGIS?

No, it is not possible to configure multifactor authentication (MFA) from multiple devices in ArcGIS Online and Portal for ArcGIS. Multifactor authentication provides an extra level of security by requiring a verification code in addition to a username and password when members log in. Only a single device can be used to register an MFA for each built-in account tied to the one-time code generated by the ArcGIS Online-supported authenticator app or the ArcGIS Enterprise-supported authenticator app installed on the registered mobile device. Refer to ArcGIS Online: Multifactor authentication and Portal for ArcGIS: Multifactor authentication for more information.

It is only possible to change the device registered to the MFA. To accomplish this, the MFA feature in the account’s ArcGIS Online or Portal for ArcGIS security settings must be disabled and re-enabled to add the new device. However, only the latest device used to activate the MFA is recognized for each login. Therefore, only one specific device can be used for MFA at a time.