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How to Setup Physical Standby Database using RMAN Backup Restore with Broker Configuration


How to Setup Physical Standby Database using RMAN Backup Restore

Assumption:
It is assumed that you already have single instance database installed and configured and you want to setup physical standby database for this primary database to protect you data from disaster recovery etc.
Installation and configuration of a single instance database using ASM is explained in following posts
Here is the details of my Primary database for which I want to configure the Physical Standby database
Hosts and Databases Used in this Example
DB_ROLE PRIMARY STANDBY
HOST_NAME test1 test2
DB_UNIQUE_NAME TST1TP TST1TS
DB_NAME TST1T TST1T
That's said lets start .....
Step1> Prepare your primary database to support physical standby database
  • Put the database in Archivelog mode
If the primary database is not already in archivelog mode, put it in archive log mode
SQL> alter system set log_archive_dest_1='location=/u01/dbatst1/stage/archive/';
System altered.


SQL> shut immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.
Total System Global Area 2147483648 bytes
Fixed Size                  8794848 bytes
Variable Size            1912605984 bytes
Database Buffers          218103808 bytes
Redo Buffers                7979008 bytes
Database mounted.
SQL> alter database archivelog;
Database altered.
SQL> alter database open;
Database altered.
SQL> archive log list;
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     4146
Next log sequence to archive   4148
Current log sequence           4148
  • Disabling Active Data Guard
NOTE: This step is optional and only needed if you don't want to use Oracle Active Dataguard Option or You don't have Licence for it. Since this is an static parameter it requires downtime.
SQL> alter system set "_query_on_physical"=FALSE scope=spfile;
System altered.
SQL> startup force;
ORACLE instance started.
Total System Global Area 2147483648 bytes
Fixed Size                  8794848 bytes
Variable Size            1912605984 bytes
Database Buffers          218103808 bytes
Redo Buffers                7979008 bytes
Database mounted.
Database opened.
SQL> show parameter "_query_on_physical"
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
_query_on_physical                   boolean     FALSE
  • Activating Standby File Management
SQL> alter system set standby_file_management=AUTO scope=both;
System altered.
SQL> show parameter standby_file_management
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
standby_file_management              string      AUTO
  • Enable forced logging
SQL> alter database force logging;
Database altered.
SQL> select force_logging from v$database;
FORCE_LOGGING
---------------------------------------
YES
Want to read more about force logging Check out Oracle Database Logging Mode and Enhancements in 18c
  • Enable Flashback
SQL> alter database flashback on;
Database altered.
SQL> select flashback_on from v$database;
FLASHBACK_ON
------------------
YES

  • Add Standby Logfile
The count of standby logfile group is always online logfile group +1
The Size of the standby logfile must be same as online logfile
Use below query to find the online lofile details 
SQL> select GROUP#,BYTES/1024/1024 "Online Loggroup Size in MB" from v$log;
    GROUP# Online Loggroup Size in MB
---------- --------------------------
         1                       2048
         2                       2048
Since I have 2 Online Log Group 2GB in size I must add 3 Standby logfile Group each 2GB.
SQL> alter database add standby logfile group 11 '+DG_TST_FRA' size 2048M;
Database altered.
SQL> alter database add standby logfile group 12 '+DG_TST_FRA' size 2048M;
Database altered.
SQL> alter database add standby logfile group 13 '+DG_TST_FRA' size 2048M;
Database altered.
  • Configure DG Broker Parameter
SQL> alter system set dg_broker_config_file1='+DG_TST_DATA/TST1T/drc1.dat';
System altered.
SQL> alter system set dg_broker_config_file1='+DG_TST_DATA/TST1T/drc2.dat';
System altered.
SQL> alter system set dg_broker_start=true;
System altered.

  • Setting Unique name
DB_UNIQUE_NAME parameter of primary and standby database must be unique. As mentioned in the beginning itself I am using TST1TP as DB_UNIQUE_NAME  for Primary database
SQL> alter system set db_unique_name='TST1TP' scope=spfile;
System altered.
SQL> startup force;
ORACLE instance started.
Total System Global Area 2147483648 bytes
Fixed Size                  8794848 bytes
Variable Size            1912605984 bytes
Database Buffers          218103808 bytes
Redo Buffers                7979008 bytes
Database mounted.
Database opened.
SQL> show parameter unique
NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

db_unique_name                       string      TST1TP

Step2> On Standby Database Server (test2) Install oracle database Binaries - same Oracle version as Primary Database
For Step by step instruction navigate to Oracle 12c Database Software Only Installation in Silent Mode
Step3> Optionally if using ASM
Install and configure ASM and ASM Diskgroups. Steps are provided at Installing and Configuring Oracle Grid Infrastructure for Standalone Server in Silent Mode
Step4> Configure Oracle Network Files
  • Configuring TNSNAMES.ORA file
Configuring tnsnames.ora file
Prepare the tns entry for both primary as well as Stanby and enter in $ORACLE_HOME/network/admin/tnsnames.ora file in both primary and physical stanby database servers
TST1TP =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP) (HOST = test1.oracle.com)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = TST1TP)
      (UR = A)
    )
  )
TST1TS =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP) (HOST = test2.oracle.com) (PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = TST1TS)
      (UR = A)
    )
  )
  • Configure Static Entries in Listener.ora file
Note1:  Static entries are only used by the Broker itself via the Broker defined StaticConnectIdentifier property.  They are NEVER to be used for any other purpose by the user.  This includes using it for the normal DGConnectIdentifier, RMAN connections or anything else.  Also note that you must never define a static entry for the Broker 'DGB' service.  That service is for the Broker exclusive use.  Also note that using the "_DGMGRL" or "_DGB" in your TNSNAMES definition is expressly forbidden.
Note2: Static "_DGMGRL" entries are no longer needed as of Oracle Database 12.1.0.2 in Oracle Data Guard Broker configurations that are managed by Oracle Restart, RAC On Node or RAC as the Broker will use the clusterware to restart an instance.
Example:

SID_LIST_LISTENER=
  (SID_LIST=
    (SID_DESC=
     (GLOBAL_DBNAME=db_unique_name_DGMGRL.db_domain)
     (ORACLE_HOME=oracle_home)
     (SID_NAME=sid_name)
    )
  )

On Primary: Enter the following Value in Listener.ora
SID_LIST_LISTENER=
  (SID_LIST=
    (SID_DESC=
     (GLOBAL_DBNAME=TST1TP_DGMGRL)
     (ORACLE_HOME=/u01/dbatst1/12.2.0.1/dbp1)
     (SID_NAME=TST1T)
    )
  )
On Standby: Enter the following Value in Listener.ora
SID_LIST_LISTENER=
  (SID_LIST=
    (SID_DESC=
     (GLOBAL_DBNAME=TST1TS_DGMGRL)
     (ORACLE_HOME=/u01/app/oracle/12.2.0.1/dbp1)
     (SID_NAME=TST1T)
    )
  )

Step5> Create pfile from Primary for standby
SQL> create pfile='/u01/dbatst1/stage/backup/initTST1T.ora' from spfile;File created.
Step6> Transfer the PFILE on Standby Server at $ORACLE_HOME/dbs$ scp /u01/dbatst1/stage/backup/initTST1T.ora oracle@test2:/u01/app/oracle/12.2.0.1/dbp1/dbs/
Step7> modify the Pfile on Standby Server as shown below
*.db_unique_name='TST1TS'
Optionally

NOTE1:-If you have different file system/ASM DISK GROUP structure between Primary and standby then modify the following parameter accordingly

db_create_file_dest='ASM_DISKGROUP OR FILESYSTEM'
db_create_online_log_dest_1='ASM_DISKGROUP OR FILESYSTEM'
db_create_online_log_dest_2='ASM_DISKGROUP OR FILESYSTEM'
NOTE2:- If you are not willing to use OMF and you have different file system/ASM DISK GROUP structure between Primary and standby then include below Parameter in you init file of Standby.
db_file_name_convert = 'DB_FILE_LOCATION_ON_PRIMARY','DB_FILE_LOCATION_ON_STANDBY'
log_file_name_convert= 'ONLINELOG_FILE_LOCATION_ON_PRIMARY','ONLINELOG_FILE_LOCATION_ON_STANDBY'


Step8> Create Required directories on Standby Server
$ mkdir -p /u01/app/admin/TST1T/adump
Step9>On Standby Server: Set the Environment variables and start the Database Instance in NOMOUNT mode
$export ORACLE_HOME=/u01/app/oracle/12.2.0.1/dbp1
$export ORACLE_SID=TST1T
$export PATH=$ORACLE_HOME/bin:$PATH
$ sqlplus "/as sysdba"

Connected to an idle instance.
SQL> create spfile from pfile;
File created.
SQL> startup nomount;
ORACLE instance started.
Total System Global Area 2147483648 bytes
Fixed Size                  8794848 bytes
Variable Size            1912605984 bytes
Database Buffers          218103808 bytes
Redo Buffers                7979008 bytes

Step 10: Transfer Primary database password file to standby database
$ scp $ORACLE_HOME/dbs/orapwTST1T oracle@test2:$ORACLE_HOME/dbs/
Rename the password file to the standby database name.
NOTE: The password file name must match the instance name/SID used at the standby site, not the DB_NAME.
Step11> Perform the Full Backup of Primary Database
$rman target /
RMAN>run
{
  ALLOCATE CHANNEL ch1 TYPE DISK MAXPIECESIZE 10G;
  BACKUP
  FORMAT '/u01/dbatst1/stage/backup/back_%U'
  DATABASE
  PLUS ARCHIVELOG
  FORMAT '/u01/dbatst1/stage/backup/back_%U';
  RELEASE CHANNEL ch1;
}
Step12> Backup Primary Database Controlfile for Standby
RMAN>run
{
allocate channel c1 type disk;
backup
FORMAT '/u01/dbatst1/stage/backup/ctrl_%U'
current controlfile for standby;
}
Step13> Copy the Backup Pieces and Controlfile Backup on Standby Server
$scp -r /u01/dbatst1/stage/backup oracle@test2:/u01/app/stage
Step14> On Standby Database Server Restore the Standby Controlfile using RMAN
$ rman target /
connected to target database: TST1T (not mounted)
RMAN> restore standby controlfile from '/u01/app/stage/backup/ctrl_bjton1bm_1_1';
Starting restore at 31-JAN-19
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=782 device type=DISK
channel ORA_DISK_1: restoring control file
channel ORA_DISK_1: restore complete, elapsed time: 00:00:08
output file name=+DG_TEST_DATA/TST1TPS/CONTROLFILE/current.316.998999959
output file name=+DG_TEST_DATA/TST1TPS/CONTROLFILE/current.309.998999961
Finished restore at 31-JAN-19
Step15> Mount the Standby Database
RMAN> sql 'alter database mount standby database';
sql statement: alter database mount standby database
released channel: ORA_DISK_1
Step16>Catalog the backup pieces to standby controlfile 
$ rman target /
connected to target database: TST1T (DBID=3422936628, not open)
RMAN> catalog start with '/u01/app/stage/backup/';
searching for all files that match the pattern /u01/app/stage/backup/
List of Files Unknown to the Database
=====================================
File Name: /u01/app/stage/backup/back_bfton186_1_1
File Name: /u01/app/stage/backup/back_bhton1b4_1_1
File Name: /u01/app/stage/backup/back_bcton15m_1_1
File Name: /u01/app/stage/backup/ctrl_bjton1bm_1_1
File Name: /u01/app/stage/backup/back_baton14k_1_1
File Name: /u01/app/stage/backup/back_beton16p_1_1
File Name: /u01/app/stage/backup/back_bgton1ai_1_1
File Name: /u01/app/stage/backup/back_bdton166_1_1
File Name: /u01/app/stage/backup/back_b9ton144_1_1
File Name: /u01/app/stage/backup/back_b7ton135_1_1
File Name: /u01/app/stage/backup/back_b6ton12l_1_1
File Name: /u01/app/stage/backup/back_bbton155_1_1
File Name: /u01/app/stage/backup/back_b8ton13k_1_1
Do you really want to catalog the above files (enter YES or NO)? yes
cataloging files...
cataloging done
List of Cataloged Files
=======================
File Name: /u01/app/stage/backup/back_bfton186_1_1
File Name: /u01/app/stage/backup/back_bhton1b4_1_1
File Name: /u01/app/stage/backup/back_bcton15m_1_1
File Name: /u01/app/stage/backup/ctrl_bjton1bm_1_1
File Name: /u01/app/stage/backup/back_baton14k_1_1
File Name: /u01/app/stage/backup/back_beton16p_1_1
File Name: /u01/app/stage/backup/back_bgton1ai_1_1
File Name: /u01/app/stage/backup/back_bdton166_1_1
File Name: /u01/app/stage/backup/back_b9ton144_1_1
File Name: /u01/app/stage/backup/back_b7ton135_1_1
File Name: /u01/app/stage/backup/back_b6ton12l_1_1
File Name: /u01/app/stage/backup/back_bbton155_1_1
File Name: /u01/app/stage/backup/back_b8ton13k_1_1

Step17> Restore the backup on Standby database using Restore command
RMAN> run
{
  ALLOCATE CHANNEL ch1 TYPE DISK;
  RESTORE DATABASE;
  RELEASE CHANNEL ch1;
Step18> From Primary Database: Create the dataguard broker configuration using dgmgrl utility
$ dgmgrl /
Welcome to DGMGRL, type "help" for information.
Connected to "TST1TP"
Connected as SYSDG.
DGMGRL> CREATE CONFIGURATION DG_TST1T AS PRIMARY DATABASE IS TST1TP CONNECT IDENTIFIER IS TST1TP;
Configuration "dg_tst1t" created with primary database "tst1tp"
DGMGRL> ADD DATABASE TST1TS AS CONNECT IDENTIFIER IS TST1TS;
Database "tst1ts" added
DGMGRL> show configuration;
Configuration - dg_tst1t
  Protection Mode: MaxPerformance
  Members:
  tst1tp - Primary database
    tst1ts - Physical standby database
Fast-Start Failover: DISABLED
Configuration Status:
DISABLED

DGMGRL> enable configuration;
Enabled.

After you create the broker configuration and add the standby database to the configuration, as soon as you will enable the configuration, the broker will set log_archive_dest parameter automatically and start the logshipping and log apply process at standby database. 
Wait for 2 min and run show configuration again. You will that the standby database is now applying the logs or is in sync with primary
DGMGRL> show configuration;
Configuration - dg_tst1t
  Protection Mode: MaxPerformance
  Members:
  tst1tp - Primary database
    tst1ts - Physical standby database
Fast-Start Failover: DISABLED
Configuration Status:
SUCCESS   (status updated 49 seconds ago)

Step19> If using Oracle Restart optionally register the database with oracle restart
$srvctl add database -db TST1TS -oraclehome /u01/app/oracle/12.2.0.1/dbp1 -spfile /u01/app/oracle/12.2.0.1/dbp1/dbs/spfileTST1T.ora -pwfile /u01/app/oracle/12.2.0.1/dbp1/dbs/orapwTST1T -role PHYSICAL_STANDBY -startoption mount
$ srvctl config database -db TST1TS
Database unique name: TST1TS
Database name:
Oracle home: /u01/app/oracle/12.2.0.1/dbp1
Oracle user: oracle
Spfile: /u01/app/oracle/12.2.0.1/dbp1/dbs/spfileTST1T.ora
Password file: /u01/app/oracle/12.2.0.1/dbp1/dbs/orapwTST1T
Domain:
Start options: mount
Stop options: immediate
Database role: PHYSICAL_STANDBY
Management policy: AUTOMATIC
Disk Groups:
Services:
OSDBA group: oinstall
OSOPER group: oinstall
Database instance: TST1TS


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