DirectAdmin determines the admin password during installation and saves these passwords into the file called setup.txt. If you havent changed this password, you can find it in this file, to see the file contents:

less /usr/local/directadmin/scripts/setup.txt

adminpass= you can find admin password here, and if you didn’t change it after installing you should be able to log in to your admin interface

to change admin password by ssh or console, write:

passwd admin

and enter your new password.