How can it be checked that a machine was sucessfully added to an Active Directory enviroment?

The `net RPC testjoin` command is not the correct syntax or utility for directly testing an Active Directory domain join status; `net ADS` is used for Active Directory specific operations.

The `tdbdump /etc/samba/secret.tdb` command displays the contents of the Samba secrets database, which stores machine account information, but it does not actively test the live domain join status or connectivity.

The `testparm -v |grep join` command is used to display and filter Samba configuration parameters related to joining, not to perform a live check of the actual domain membership status with Active Directory.

The `net ADS testjoin` command is a Samba utility designed specifically to check the current status of a Samba machine's membership in an Active Directory domain, ensuring that it can communicate and authenticate correctly with the domain controllers.