Oracle Smear Oracle Learning Note Chapter 10th Data Guard says, I'm just backing up

DG is a backup recovery tool, but more strictly the meaning of it is disaster recovery

Data Guard is a collection of one primary database and one or more standby databases, divided into two classes of logical standby and physical standby

10.2.1 preparation of physical standb before creation

Whether it is physical standb or logical standby, its creation is dependent on the primary database, so the most important part of the preparation is to configure the primary database

10.2.1.1 Enable Force Logging (forced logging mode)

sql> ALTER DATABASE force logging;

10.2.1.2 creating a secret key file

All databases in the same data guard configuration must have a separate key file, and the SYS user of all database servers has the same password, ensuring that the redo data is transferred smoothly because redo is transmitting redo data through authenticated network sessions, The session is validated with the user password of the SYS contained in the secret key file.

Orapwd FILE=/HOME/ORACLE/APP/ORACLE/PRODUCT/11.2.0/DB_1/DATABASE/ORAPWORCL Password=verysafe entries=30

File: Specify the secret key file name and path

Password:sys User Password

Entries: Specifies the maximum number of users that a database can have SYSDBA permissions

Naming rules for file Orapw[sid]

10.2.1.3 Configuration Standby Redologs

1 About standby Redologs

Oracle recommends that DBAs consider Standby redologs configuration issues when creating Standby databases. Standby Redologs is very similar to online redolog, it should be said that the two are just different service objects, other parameters, attributes, Even the command format of the operation is almost the same.

(1) Ensure that the file size of the standby redologs is the same size as the online redologs file of the primary database, for ease of reception and application.

(2) Create an appropriate number of log groups. In general, the Standby redologs log group is one less than the online redologs log group of the primary database.

2 Management Standby Redologs

The Standby redologs is almost identical to the online redologs, but you need to specify a Standby parameter when creating or deleting

Add a new standby group, do not repeat the group number with online

ALTER DATABASE ADD standby logfile Group 4 ('/home/oracle/app/oracle/oradata/orcl/standbyrd01.log ') size 51M;

Delete Yes

ALTER DATABASE drop standby logfile Group 4;

View with Dynamic view

Select group#, type,member from V$logfile;

　　

View the standby created by the current database by standby redologs private View Redologs

Select Group#,thread#,sequence#,archived,status from V$standby_log;

　　

Why primary need to prepare standby redologs, because once need to switch primary can become standby continue to work, although now useless but discouragement will use later.

10.2.1.4 Setting Initialization parameters

For primary databases, there are several role-related initialization parameters that need to be configured, which are initially used to control the Redo transport service. It is recommended to configure both primary and standby

10.2.1.5 placing the primary database in archive mode

Other articles are introduced

　

Oracle Smear Oracle Learning Note Chapter 10th Data Guard says, I'm just backing up