由于是重建,原来DG环境中被重建的物理从库中的数据文件，日志文件，dump文件等都可以删除，切记原来的参数文件和相应目录一定要保存。
主库做standby控制文件和数据库的全备份
备份控制文件
RMAN> backup current controlfile for standby format '/u01/rman_recover/ctlfile.bak';
备份整库
RMAN> backup database format '/u01/rman_recover/%full_backup_%T_%t.bak';
备库上查找控制文件路径：
SQL> select name from v$controlfile;
NAME
---------------------------------------------
/u01/app/oracle/oradata/orcl_s/control01.ctl
/u01/app/oracle/oradata/orcl_s/control02.ctl
/u01/app/oracle/oradata/orcl_s/control03.ctl
SQL> shutdown abort
ORACLE instance shut down.
copy主库的备份到备库
[oracle@localhost ~]$ scp 10.37.11.11:/u01/rman_recover/*.bak /u01/rman_recover/
oracle@10.37.11.11's password:
0ull_backup_20140522_848228743.b 100% 7072KB 6.9MB/s 00:00
7ull_backup_20140522_848228595.b 100% 1002MB 11.9MB/s 01:24
ctlfile.bak 100% 7040KB 6.9MB/s 00:01
将控制文件copy到原配置中：
[oracle@localhost rman_recover]$ cp ctlfile.bak /u01/app/oracle/oradata/orcl_s/control01.ctl
[oracle@localhost rman_recover]$ cp ctlfile.bak /u01/app/oracle/ora
data/orcl_s/control02.ctl
[oracle@localhost rman_recover]$ cp ctlfile.bak /u01/app/oracle/ora
data/orcl_s/control03.ctl
启动备库实例：
SQL> startup nomount
ORACLE instance started.
Total System Global Area 167772160 bytes
Fixed Size 1218316 bytes
Variable Size 75499764 bytes
Database Buffers 88080384 bytes
Redo Buffers 2973696 bytes