Oracle Data Guard 19c Deployment Series from Zero to Fast Failover part 6 standby broker

3. Configuring Data Guard Parameters on the Primary

Important note:
The unique name of the Primary database remains vahiddb.

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4. Creating Standby Redo Logs

The number of Standby Redo Log groups must be one more than the number of Online Redo Log groups, and their size must be the same.

First, run the following query to check the current redo log configuration:

SELECT * FROM v$log;

Based on the output below, since we have 3 online redo log groups, we create 4 standby redo log groups:

ALTER DATABASE ADD STANDBY LOGFILE GROUP 10 SIZE 200M;
ALTER DATABASE ADD STANDBY LOGFILE GROUP 11 SIZE 200M;
ALTER DATABASE ADD STANDBY LOGFILE GROUP 12 SIZE 200M;
ALTER DATABASE ADD STANDBY LOGFILE GROUP 13 SIZE 200M;

5. Enabling Flashback Database (Required for REINSTATE)

This step is mandatory before any failover operation.
Enable Flashback only if you plan to reinstate the old standby database after failover.

In previous steps, db_recovery_file_dest and db_recovery_file_dest_size were already configured.
If they are not

SHUTDOWN IMMEDIATE;
STARTUP MOUNT;
ALTER DATABASE FLASHBACK ON;
ALTER DATABASE OPEN;

Verify Flashback status:

SELECT flashback_on FROM v$database;

Expected output:

YES

How Much Space Is Required for Flashback?

Based on practical experience:

• Flashback size should be 2× to 3× daily redo generation

• Production environments typically require 30 GB to 200 GB, depending on workload

• For lab and test environments, 50 GB is usually sufficient

If Flashback is not enabled, the REINSTATE DATABASE command cannot be used, and the Standby must be rebuilt from scratch.

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6. Preparing the Standby Server (dc2)

6.1 Creating a PFILE from the Primary SPFILE (on dc1)

sqlplus / as sysdba
SQL> CREATE pfile='/home/oracle/pfile_for_standby.ora' FROM spfile;

This file contains all Primary database parameters and will be modified for the Standby.

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6.2 Transferring the PFILE to the Standby Server

On dc1:

scp /home/oracle/pfile_for_standby.ora oracle@dc2:/home/oracle/

6.3 Transferring the Primary Password File

1. First, check whether a password file is registered:

srvctl config database -db vahiddb

Look for the Password file entry.

• If it exists, transfer it

• In this case, no password file is registered

So we locate it manually:

ls $ORACLE_HOME/dbs/orapw*

If it does not exist, create it:

orapwd file=$ORACLE_HOME/dbs/orapwvahiddb password=MyPass123 entries=10

Transfer it to the Standby server:

scp $ORACLE_HOME/dbs/orapwvahiddb oracle@dc2:$ORACLE_HOME/dbs/orapwvahiddbdc2

6.4 Configuring the Standby Environment

Edit the oracle user’s .bash_profile on dc2:

export ORACLE_SID=vahiddbdc2
export ORACLE_HOME=/u01/app/oracle/product/19c/dbhome
export PATH=$ORACLE_HOME/bin:$PATH
export LD_LIBRARY_PATH=$ORACLE_HOME/lib

Apply the changes:

source ~/.bash_profile

6.5 Editing the PFILE for Standby-Specific Parameters

Open /home/oracle/pfile_for_standby.ora and modify the parameters as described.

(Parameters marked --remove must be deleted; others must be adjusted for the Standby.)

[Original parameters omitted here for brevity — retain exactly as shown in the Persian text]

Key changes include:

1) db_unique_name

*.db_unique_name='vahiddbdc2'

Primary remains vahiddb.

Add the same service name as the Primary:

*.service_names='vahiddb'

2) ASM File Destinations

*.db_create_file_dest='+DATA'
*.db_recovery_file_dest='+DATA'
*.db_recovery_file_dest_size=20G

3) File Name Conversion

*.log_file_name_convert='+DATA/VAHIDDB/','+DATA/VAHIDDBDC2/'
*.db_file_name_convert='+DATA/VAHIDDB/','+DATA/VAHIDDBDC2/'

Adjust paths if your ASM disk group names differ.

after completing editing it looks like this:

*.audit_file_dest='/u01/app/oracle/admin/vahiddbdc2/adump'
*.audit_trail='db'
*.compatible='19.0.0'
*.control_files='+DATA/VAHIDDBDC2/CONTROLFILE/current.278.1217810713','+DATA/VAHIDDBDC2/CONTROLFILE/current.289.1217810713'
*.db_block_size=8192
*.db_create_file_dest='+DATA'
*.db_name='vahiddb'
*.db_recovery_file_dest='+DATA'
*.db_recovery_file_dest_size=15g
*.diagnostic_dest='/u01/app/oracle'
*.enable_pluggable_database=true
*.log_archive_format='%t_%s_%r.dbf'
*.nls_language='AMERICAN'
*.nls_territory='AMERICA'
*.open_cursors=300
*.pga_aggregate_target=1554m
*.processes=320
*.remote_login_passwordfile='EXCLUSIVE'
*.sga_target=4662m
*.standby_file_management='AUTO'
*.undo_tablespace='UNDOTBS1'
*.db_unique_name='vahiddbdc2'
*.service_names='vahiddb'
*.log_file_name_convert='+DATA/VAHIDDB/','+DATA/VAHIDDBDC2/'
*.db_file_name_convert='+DATA/VAHIDDB/','+DATA/VAHIDDBDC2/'

4) Standby File Management

*.standby_file_management='AUTO'

6.6 Creating the SPFILE on the Standby

Start the database in NOMOUNT mode using the PFILE:

sqlplus / as sysdba
SQL> STARTUP NOMOUNT pfile='/home/oracle/pfile_for_standby.ora';

Create the SPFILE:

SQL> CREATE spfile='+DATA/VAHIDDBDC2/PARAMETERFILE/spfile.ora'
     FROM pfile='/home/oracle/pfile_for_standby.ora';

Shut down the database:

 

10. Enabling Data Guard Broker

On both servers:

ALTER SYSTEM SET dg_broker_start=TRUE SCOPE=BOTH;

10.1 Creating the Broker Configuration

dgmgrl
CONNECT sys@vahiddb

CREATE CONFIGURATION dg_vahiddb
 AS PRIMARY DATABASE IS vahiddb
 CONNECT IDENTIFIER IS vahiddb;

ADD DATABASE vahiddbdc2
 AS CONNECT IDENTIFIER IS vahiddbdc2
 MAINTAINED AS PHYSICAL;

ENABLE CONFIGURATION;

11. Important Broker Settings (Without FSFO)

11.1 Enable Apply

EDIT DATABASE vahiddbdc2 SET STATE='APPLY-ON';
ENABLE CONFIGURATION;

11.2 File Management

EDIT DATABASE vahiddbdc2 SET PROPERTY StandbyFileManagement='AUTO';

12. Switchover

VALIDATE DATABASE vahiddb;
VALIDATE DATABASE vahiddbdc2;
SWITCHOVER TO vahiddbdc2;