This example configures automatic disk channels across two file systems:

CONFIGURE DEVICE TYPE DISK PARALLELISM 2;
CONFIGURE CHANNEL 1 DEVICE TYPE DISK FORMAT '/disk1/%U';
CONFIGURE CHANNEL 2 DEVICE TYPE DISK FORMAT '/disk2/%U';

Because PARALLELISM is set to 2, the following command divides the backup pieces between two file systems:

BACKUP DEVICE TYPE DISK
  DATABASE PLUS ARCHIVELOG;

The following LIST command shows how the data file backup was parallelized:

RMAN> LIST BACKUPSET 2031, 2032;
 
List of Backup Sets
===================
 
BS Key  Type LV Size       Device Type Elapsed Time Completion Time
------- ---- -- ---------- ----------- ------------ ---------------
2031    Full    401.99M    DISK        00:00:57     19-JAN-07
        BP Key: 2038   Status: AVAILABLE  Compressed: NO  Tag: TAG20070119T100532
        Piece Name: /disk1/24i7ssnc_1_1
  List of Datafiles in backup set 2031
  File LV Type Ckp SCN    Ckp Time  Name
  ---- -- ---- ---------- --------- ----
  1       Full 973497     19-JAN-07 /disk3/oracle/dbs/t_db1.f
  5       Full 973497     19-JAN-07 /disk3/oracle/dbs/tbs_112.f
 
BS Key  Type LV Size       Device Type Elapsed Time Completion Time
------- ---- -- ---------- ----------- ------------ ---------------
2032    Full    133.29M    DISK        00:00:57     19-JAN-07
        BP Key: 2039   Status: AVAILABLE  Compressed: NO  Tag: TAG20070119T100532
        Piece Name: /disk2/25i7ssnc_1_1
  List of Datafiles in backup set 2032
  File LV Type Ckp SCN    Ckp Time  Name
  ---- -- ---- ---------- --------- ----
  2       Full 973501     19-JAN-07 /disk3/oracle/dbs/t_ax1.f
  3       Full 973501     19-JAN-07 /disk3/oracle/dbs/t_undo1.f
  4       Full 973501     19-JAN-07 /disk3/oracle/dbs/tbs_111.f