Installation Directory of the Database Software: -R 
Use
Option in the Database Manager CLIOn servers that contain several versions of the database system software it is necessary to address the correct version of the database. Enter the path of the desired version under
<inst_path>.Syntax
-R <inst_path>

dbmcli -R "C:\Program Files\SAP DBTech\V72"
When you set up a session there is a check whether the specified version on the server is recorded in the list of registered versions. If it is not, the session connection is refused.

When calling the Database Manager CLI using option
-R, a specified database version can only be connected if the database installation has been correctly registered.If you specify the option
-d and the name of a database instance in addition to the option –R, option -R is ignored. In this case, the Database Manager CLI uses the version of the database software assigned to the specified database instance.