Martin Lerch - 2019-05-08

Hello. I have a peculiar problem that must have started just recently, but I can't figure out what it is. I have 4 servers.

  • 3 centOS 7 and 1 centOS6.
  • All servers have webmin installed.
  • All webmin installations are set up the same, with the same main users.
  • All users use Google 2-factor authentication. They are all set up with the same QR code.
  • The system time is set correctly on all servers and is the same.

On the centOS 6 server all of a sudden, when I try to log in I get this error message:
Warning!
Two-factor authentication failed : Incorrect OTP code

On all other centOS 7 servers I am able to log in with the very same auth code without an issue! What is going on?

Does anyone know how I could track this down on the centOS 6 server and why it is not working? When I disable 2-factor authentication I can log in to centOS 6.10 webmin server just fine. But as soon as I set up 2-Factor authentication and log out and try to log back in using username, pass and auth code I get the error message.

Please advise.

Thanks.