Hi,
this is described in Command Line Interface Reference guide:
Possible return values of commands are:
1 Program failed, command syntax error.
2 Program failed, invalid argument.
3 Program failed, internal error.
4 Program failed, reason unknown.
Some commands may return additional error messages. These are
described in individual reference pages.
Additional return values of the omnib command are:
10 - There was an error while backing up some files. All agents completed successfully.
11 - One or more agents failed, or there was a database error.
12 - None of the agents completed the operation; session was aborted by Data Protector.