Configure Standby Redo Log for Data Guard

Data Guard configures Standby Redo Log Data Guard in maximum protection and maximum availability mode, for real-time use of the maximum performance mode, the Standby database must be configured with the Standby Redo Log www.2cto.com slave database to create and configure the Standby Redo Log to receive logs transmitted from the master database, the Standby Redo Log is used to restore the master database from being created and configured to receive the original slave database after the master/Slave switchover (the master database after the switchover) the principle of creating a Standby Redo Log is as follows: ① The file size of Standby Redo Log is the same as that of the online redo log file of the master database ② the number of Standby Redo Log file groups is calculated according to the following principles: standby redo log group formula> = (number of log groups for each instance + 1) * Number of instances. For example, in my environment, there is only one node, and this node has three redo groups, therefore, the formula for the number of Standby redo log groups is> = (3 + 1) * 1 = 4. Therefore, four Standby redo log groups must be created. ③ each log group must be secure, the following uses the master database configuration Standby Redo Log as an example to describe how to configure multiple images: [SQL] sys @ ORCL> alter database add standby logfile group 4 ('/u01/app/oracle/oradata/ORCL/stdredo001.log') size 50 M; Database altered. sys @ ORCL> alter database add standby logfile group 5 ('/u01/app/oracle/oradata/ORCL/stdredo002.log') size 50 M; Database altered. sys @ ORCL> alter database add standby logfile group 6 ('/u01/app/oracle/oradata/ORCL/stdredo003.log') size 50 M; Database altered. sys @ ORCL> alter database add standby logfile group 7 ('/u01/app/oracle/oradata/ORCL/stdredo004.log') size 50 M; Database altered. (ii) method for deleting Standby Redo Log Standby redo log: [SQL] sys @ ORCL> alter database drop standby logfile group 8; Database altered. (3) query the Standby Redo Log file group in the V $ STANDBY_LOG view: [plain] sys @ ORCL> select group #, thread #, sequence #, archived, status from v $ standby_log; GROUP # THREAD # SEQUENCE # arc status ---------- --- ---------- 4 0 0 0 yes unassigned 5 0 yes unassigned 6 0 yes unassigned 7 0 0 YES UNASSIGNED