The global catalog is a distributed data repository that facilitates searching and logons in an Active Directory® Domain Services (AD DS) directory service forest.
I cannot see “Unix attribute” tab in Active Directory on Windows Server 2012 R2 even after installing IdMU.
Identity Management for Unix enables you to integrate Windows users into an existing Unix or LInux environment, including managing user accounts, passwords on Windows and Unix systems.
Active Directory Recycle bin in Windows Server 2012 R2 – is a great feature for System Administrator in the event of recovery deleted objects from Active Directory. This feature is available in server since version 2008 but it is not enabled by default. You have to enable it before you can use it.