Note (2026): this post from 2017 was left unfinished — it announced the steps but never provided them. The complete content, updated for the current method with
realmd and sssd, is in Integrating Ubuntu into Active Directory. This page remains online because its address is already indexed.Integrating an Ubuntu machine into a Windows Active Directory domain requires, in short: pointing the client's DNS to the domain controller, setting a consistent hostname in /etc/hostname and /etc/hosts, having the domain name and an account with permission to join machines.
The approach in 2017 involved samba, winbind and manually editing krb5.conf, smb.conf and nsswitch.conf. Today the process is much shorter — realm discover, realm join and the sssd taking care of the rest — and is explained with the complete commands and login verification in the main post: