11g active data guard实现备库rman备份，这样可以在不影响主库对外服务的情况下，实现数据库的备份。
11g active data guard实现备库rman备份，，这样可以在不影响主库对外服务的情况下，实现数据库的备份。
测试如下：
sql> select open_mode,protection_mode,protection_level,database_role from v$database;
open_mode            protection_mode      protection_level    database_role
-------------------- -------------------- -------------------- ----------------
read only with apply maximum availability maximum availability physical standby
sql> exit
disconnected from oracle database 11g enterprise edition release 11.2.0.3.0 - 64bit production
with the partitioning, olap, data mining and real application testing options
@pekdc1-vcm-04: [/flashbackfile/vcm01/vcm01_b/backupset/2014_03_04] 
$rman target /
recovery manager: release 11.2.0.3.0 - production on tue mar 4 17:01:40 2014
copyright (c) 1982, 2011, oracle and/or its affiliates.  all rights reserved.
connected to target database: vcm01 (dbid=1142584794)
rman> backup database;
starting backup at 04-mar-14
using target database control file instead of recovery catalog
allocated channel: ora_disk_1
channel ora_disk_1: sid=2280 device type=disk
channel ora_disk_1: starting full datafile backup set
channel ora_disk_1: specifying datafile(s) in backup set
input datafile file number=00005 name=/datafile/vcm01/htz_data01.dbf
input datafile file number=00002 name=/datafile/vcm01/sysaux01.dbf
input datafile file number=00008 name=/datafile/vcm01/vats_dat01.dbf
input datafile file number=00004 name=/datafile/vcm01/dba_ts01.dbf
input datafile file number=00001 name=/datafile/vcm01/system01.dbf
input datafile file number=00006 name=/datafile/vcm01/htz_index01.dbf
input datafile file number=00003 name=/datafile/vcm01/undotbs01.dbf
input datafile file number=00007 name=/datafile/vcm01/user_ts_moni_11b01.dbf
input datafile file number=00009 name=/datafile/vcm01/user_ts_moni_12b01.dbf
input datafile file number=00010 name=/datafile/vcm01/user_ts_moni_13a01.dbf
channel ora_disk_1: starting piece 1 at 04-mar-14
channel ora_disk_1: finished piece 1 at 04-mar-14
piece handle=/flashbackfile/vcm01/vcm01_b/backupset/2014_03_04/o1_mf_nnndf_tag20140304t170146_9kc5mv98_.bkp tag=tag20140304t170146 comment=none
channel ora_disk_1: backup set complete, elapsed time: 00:00:25
channel ora_disk_1: starting full datafile backup set
channel ora_disk_1: specifying datafile(s) in backup set
including current control file in backup set
including current spfile in backup set
channel ora_disk_1: starting piece 1 at 04-mar-14
channel ora_disk_1: finished piece 1 at 04-mar-14
piece handle=/flashbackfile/vcm01/vcm01_b/backupset/2014_03_04/o1_mf_ncsnf_tag20140304t170146_9kc5nofm_.bkp tag=tag20140304t170146 comment=none
channel ora_disk_1: backup set complete, elapsed time: 00:00:01
finished backup at 04-mar-14
rman>
推荐阅读：
rman 配置归档日志删除策略
oracle基础教程之通过rman复制数据库
rman备份策略制定参考内容
rman备份学习笔记
oracle数据库备份加密 rman加密