is it possible to
- stop the database
- copy all files and subdirectories from /usr/lib/oracle to another machine with the same hostname and ip-adress
- start the datatbase
Would that work?
I'll agree too, sort of. Stopping the database is the critical part- a shutdown database is the only way to get a consistent backup. There are other ways to backup datafiles, i.e. a "hot" backup but that requires enabling archivelog mode, putting the database in backup mode, copying the datafiles to the new host, and performing recovery to get all datafiles consistent at the new host. The archivelog files created during the backup will be required at the new host for the recovery.
With a "cold" backup (database shutdown) the recovery part is not needed.
And the "to another machine with the same hostname and ip-adress" part will be a problem- can't have two hosts on the network with the same IP. At least not at the same time, two machines with the same IP is a not healthy state for the LAN.
For a new host, use a new hostname, that is a small part of the network client configuration.