When you see the error “Terminating with error code 12” (R3trans exit code 12), run R3trans connection test manually:
Connect the Console Operating System (Linux/AIX/Windows).
# su – <SID>adm
$ R3trans -d -w $HOME/dbconn.log
$ cat $HOME/dbconn.log
The R3trans error output will contain detailed information.
Note.: Usually this occurs at the expiration of the Oracle user password (11g onwards).