Duo has thorough documentation for adding MFA to your SSH sessions, but there are a couple additional steps needed to also integrate with Active Directory. This post will go through the installation for both Duo and Active Directory for Ubuntu 16.04. For other Linux distros, the Duo documentation linked above has you covered.
- Ubuntu 16.04 server
- Duo MFA account
- Duo Unix package
- Centify Express for Active Directory integration
Install OpenSSL development headers and libraries: