Problem:

/etc/oraInst.loc points to an Inventory that does not exist:

mkdir : No such file or directory at ./adclone.pl line 1274

ERROR: Failed to execute ./adclone.pl

Solution:

As root user, ran /tmp/orainstRoot.sh.

Reran clone again, but it failed.

The root directory had completely filled up because the backup was restored to /oracle and not /u0/oracle. Removed /oracle, then reran /tmp/orainstRoot.sh and tried script again.