一、步骤
1.关闭节点二
2.配置相关参数
3.关闭节点1
4.启用闪回
5.打开节点二
创新互联是一家专业的成都网站建设公司，我们专注网站建设、成都网站设计、网络营销、企业网站建设，买友情链接，1元广告为企业客户提供一站式建站解决方案，能带给客户新的互联网理念。从网站结构的规划UI设计到用户体验提高，创新互联力求做到尽善尽美。
二、操作过程
[root@rac01 ~]# su - oracle
Last login: Thu Jan 4 10:33:31 CST 2018 on pts/2
$sqlplus / as sysdba
SQL*Plus: Release 12.1.0.2.0 Production on Fri Jan 5 18:52:55 2018
Copyright (c) 1982, 2014, Oracle. All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Advanced Analytics and Real Application Testing options
SYS@orcl1>
SYS@orcl1>
SYS@orcl1>
SYS@orcl1> show parameter recovery
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest string
db_recovery_file_dest_size big integer 0
recovery_parallelism integer 0
SYS@orcl1> show parameter flashback
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_flashback_retention_target integer 1440
SYS@orcl1> alter system set db_recovery_file_dest_size=1g;
System altered.
SYS@orcl1> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination +DATADG
Oldest online log sequence 121
Next log sequence to archive 122
Current log sequence 122
SYS@orcl1> alter system set db_recovery_file_dest='+datadg';
System altered.
SYS@orcl1> alter system set db_flashback_retention_target=2880;
System altered.
SYS@orcl1> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SYS@orcl1> startup mount;
ORACLE instance started.
Total System Global Area 1241513984 bytes
Fixed Size 2923872 bytes
Variable Size 620757664 bytes
Database Buffers 603979776 bytes
Redo Buffers 13852672 bytes
Database mounted.
SYS@orcl1> alter database flashback on;
Database altered.
SYS@orcl1> alter database open;
Database altered.
SYS@orcl1> select flashback_on from v$database;
FLASHBACK_ON
------------------
YES
SYS@orcl1> show parameter recovery
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest string +datadg
db_recovery_file_dest_size big integer 1G
recovery_parallelism integer 0
SYS@orcl1> show parameter flashback
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_flashback_retention_target integer 2880
SYS@orcl1> 小结：
生产环境ADG备库开闪回解决逻辑错误。未来再添加一个备库，做灾备，一主两备哈
