How to Migrate Oracle 11g R2 (Windows) database to Oracle 12c R2 (Linux) db
Source:

RMAN&gt; shutdown immediate
RMAN&gt; startup mount
RMAN&gt; backup database ...


Destination:

RMAN&gt; startup nomount
RMAN&gt; restore controlfile from ...
RMAN&gt; alter database mount;
RMAN&gt; restore database;
RMAN&gt; alter database open resetlogs upgrade;


Then manually upgrade the database to 12.2:

Example of Manual Upgrade of Windows Non-CDB Oracle Database 11.2.0.3