Adding the KNTAUser attribute to users on an LDAP server is a convenient way to mark users for importing. However, it is not a required step for LDAP-PPM Center integration.
When importing user from LDAP into PPM Center, the parameter LDAP Import PPM User Only can be set to No, and the Search Filter field used to query for the attribute of your choice.
If LDAP Import PPM User Only is set to Yes on the Import Users report, only the LDAP users with the KNTAUser attribute are imported.
To apply the KNTAUser attribute to users on an LDAP server, it is necessary to run a command locally on the server machine.