Hi Ichtouk
the sqlplus command host does not allow you to execute commands on the server you're connected to. Instead, you can execute local command without leaving your current sqlplus session.
It is by no means an open window to the Oracle servers O/S (would be bad, don't you think?).
Having said that, SAP HANA does not include a SSH client in the database client software.
If you want to access the SAP HANA server on O/S level, you really need to use a proper SSH client with a regular O/S user logon.
- Lars