undo_tablespace block damaged.

SQL> STARTUP MOUNT

SQL> alter database datafile '/data/oradata/VISAOEM/undotbs01.dbf' offline drop;

SQL> alter system set undo_management=manual scope=spfile;

SQL> CREATE UNDO TABLESPACE UNDOTBS3 DATAFILE
  '/data1/oradata/VISAOEM/undotbs02.dbf' SIZE 1120M AUTOEXTEND ON NEXT 200M MAXSIZE 16384M
ONLINE
RETENTION NOGUARANTEE
BLOCKSIZE 8K
FLASHBACK ON;
SQL> alter system set undo_tablespace=undotbs2 scope=spfile;

SQL> SHUTDOWN

SQL> startup
SQL> show parameter undo_tablespace;
SQL> select owner, segment_name,tablespace_name,status from dba_rollback_segs;

SQL> CREATE PFILE='/tmp/pfilevisaoem.ora' from spfile;


vi /tmp/pfilevisaoem.ora

--------------------------------------------------------------------------------------------------
_corrupted_rollback_segments=(_SYSSMU1$,_SYSSMU2$,_SYSSMU3$,_SYSSMU4$,_SYSSMU5$,_SYSSMU6$,_SYSSMU7
$,_SYSSMU8$,_SYSSMU9$,_SYSSMU10$,_SYSSMU11$,_SYSSMU12$,_SYSSMU13$,_SYSSMU14$,_SYSSMU15$,_SYSSMU16$
,_SYSSMU17$,_SYSSMU18$,_SYSSMU19$)
--------------------------------------------------------------------------------------------------

SQL> startup restrict pfile='/tmp/pfilevisaoem.ora'

SQL> drop tablespace undotbs1 including contents and datafiles;

SQL> alter system set undo_management=auto scope=spfile;



SQL> SHUTDOWN

SQL> startup