You want to use Acronis Cyber Infrastructure Backup Gateway to connect storage backend to Acronis Cyber Cloud. You have two-factor authentication (2FA) enabled for the cloud tenant where you want to register this storage and this tenant's users.
Manual ACI Backup Gateway registration in Acronis Cyber Cloud per Backup Gateway Quick Start Guide fails with the following error in UI:
Incorrect username or password.
In the same way deployment of Backup Gateway in Azure per Backup Gateway Quick Start Guide for Microsoft Azure fails and the following message is observed in /var/log/initializing log of deployed Azure VM:
[root@acronis-gateway ~]# tail -n2 /var/log/initializing
[2020-05-05T17:03:56+0000]: Registering this instance as storage in cloud...
Current implementation of Backup Gateway service does not support registration under users having 2FA enabled.
Disable 2FA for a specific user within a 2FA-enabled tenant as described in User Guide. Use that user’s credentials to register your storage.
Other users of the account can keep using two-factor authentication.