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PRIMARY- primdb
STANDBY -standdb
Ensure that the primary database is in: 1) FORCE LOGGING must be enabled SQL> select force_logging from v$database; 2)ARCHIVELOG mode, that automatic archiving is enabled. SQL> archive log list 3) MAXLOGFILES >= (2 * Current Redo Log Groups) + 1: SQL> select records_used "Current Groups", records_total "Max Groups" from v$controlfile_record_section where type = 'REDO LOG'; 4) Configure spfile file if not already configured
ALTER DATABASE FORCE LOGGING; Create a directory structures in standby server. LOG_ARCHIVE_DEST_STATE_1=ENABLE LOG_ARCHIVE_DEST_STATE_2=ENABLE Create a Control File for the Standby Database ALTER DATABASE CREATE STANDBY CONTROLFILE AS ‘/yourdir/control1.ctl’;
Copy and paste in respect control file directories in standby database server.
Take a cold backup of all datafiles,logfiles and put into
Corresponding datafile directory.
Create password file Orapwd file=$ORACLE_HOME/dbs/pwdprimdb.ora Password=mypass entries=5
Orapwd file=$ORACLE_HOME/dbs/pwdstanddb.ora Password=mypass entries=5 Password must be same for both primary & standby
Prepare the Initialization Parameter Copy and paste in respect pfile directories in standby database server CREATE PFILE=’/yourdir/initstanddb.ora’ FROM SPFILE; Parameters need to change: ######## Instance ############ db_name=primdb
db_name=primdb
instance_name= primdb
instance_name=standdb control_files=’/.../standby/control_01.ctl’ remote_login_passwordfile=exclusive
######## File Management ############ db_file_name_convert=(’.../oradata/primdb/data1/’,’.../oradata/standdb/data1/’, log_archive_dest_1=(’LOCATION=/disk1/oracle /oradata/primdb/arch’) log_archive_dest_2=(‘SERVICE=standdb lgwr sync’) FAL_SERVER=standdb FAL_CLIENT=primdb remote_login_passwordfile=exclusive
’.../oradata/primdb/data2/’,’.../oradata/standdb/data2/’) log_file_name_convert==(’.../oradata/primdb/logsa/’,’.../oradata/standdb/logsa/’, ’.../oradata/primdb/logsb/’,’.../oradata/standdb/logsb/’) standby_file_management=AUTO
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Within 2 hours U CAN Become a Dataguard Implementer ######## Archive Management ############ log_archive_start=TRUE
# The following parameter is required only if the primary and standby databases
standby_archive_dest=’/disk1/oracle/oradata/standdb/arch’ log_archive_format=log%d_%t_%s.arc log_archive_dest_1=(’LOCATION=/disk1/oracle/oradata/standdb/arch’)
#are located on the same system. lock_name_space=primdbe
log_archive_dest_2=(‘SERVICE=primdb lgwr sync’) #For manuall switchover remote_archive_enable=TRUE
Example implemented pfile:
initprimdb.ora
#Standby parameters FAL_SERVER=primdb FAL_CLIENT=standdb
#Note: #All location related parameters , need to be changed respect to the directories created standby database (i.e udump,bdump…)
# The following parameter is required only if the primary and standby databases #are located on the same system. lock_name_space=standdb
Example implemented pfile:
initstanddb.ora
Create Oracle Net Service Names for standby database (Having both Primary & Standby database tns entries is standard practice)
Create Oracle Net Service Names for primary database (Having both Primary & Standby database tns entries is standard practice)
configure a listener for the respective databases and restart the listener
configure a listener for the respective databases and restart the listener Enable dead connection detection: SQLNET.EXPIRE_TIME=2 Start the Physical Standby Database
STARTUP NOMOUNT pfile=’/.../standby/pfile/initstanddb.ora’; ALTER DATABASE MOUNT STANDBY DATABASE; Configure spfile file .
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Initiate Logshipping to the Physical Standby Database ALTER SYSTEM SWITCH LOGFILE; Verifying Standby Archive destination log shipping:
Initiate Log Apply Services
Select status,error from v$archive_dest where dest_id=2;
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT SESSION; This query includes the DISCONNECT FROM SESSION option so that log apply services run in a background session. Verifying the Physical Standby Database Identify the existing archived redo logs.
SELECT SEQUENCE#, FIRST_TIME, NEXT_TIME FROM V$ARCHIVED_LO ORDER BY SEQUENCE#; Verify that the new archived redo log was applied. SELECT SEQUENCE#,APPLIED FROM V$ARCHIVED_LOG ORDER BY SEQUENCE#; SELECT SEQUENCE#,STATUS FROM V$MANAGED_STANDBY;
SWITCH OVER Preparing for a Switchover Ensure LOG_ARCHIVE_DEST_2 parameter to point back to the primary database: Sho parameter log_archive_dest_2 log_archive_dest_2=(‘SERVICE=primdb lgwr sync’)
Add Standby Redo Log Groups to Standby Database alter database recover managed standby database cancel; alter database open read only; select max(group#) maxgroup from v$logfile; #IF max groups is 3 means create a standby group as 4,5,6 select max(bytes) / 1024 "size (K)" from v$log; #Set same size for standby logfiles. alter database add standby logfile group 4 (…\REDO04.log') size 100m; alter database add standby logfile group 5 (…\REDO04.log') size 100m; alter database add standby logfile group 6 (…\REDO04.log') size 100m;
select vs.group#,vs.bytes,vl.member from v$standby_log vs,v$logfile vl where vs.grou vl.group# order by vs.group#,vl.member;
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Add Tempfile To Standby alter tablespace temp add tempfile '…/temp_PROD_01.dbf' size 400m reuse;
Switch back to Recovery Mode: alter database recover managed standby database disconnect from session; Add Standby Redo Log Groups to Primary Database Follow the same steps mentioned in the above “Add Standby Redo Log Groups to Standby Database”
Switch To Maximum Availability Protection Mode Ensure log_archive_dest_2 must show LGWR SYNC shutdown normal startup mount alter database set standby database to maximize availability; alter database open; select protection_mode from v$database;
Test Updates Propagating to Standby
(wait a few seconds first):
Update some tables;
Go to Open Mode:
commit;
alter database recover managed standby database cancel;
alter system switch logfile;
alter database open read only; select * from (particular table which was updated in primary); Go back to Recovery Mode: alter database recover managed standby database disconnect from session;
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Ready To Switch Over Ensure all activities on the primary and standby database are ended select database_role,switchover_status from v$database; #It should return Database_role=PRIMARY & switchover_status = SESSIONS ACTIVE alter database commit to switchover to physical standby with session shutdown; shutdown immediate; startup nomount; alter database mount standby database;
alter database recover managed standby database cancel; alter database commit to switchover to primary with session shutdown; shutdown normal; startup;
alter database recover managed standby database disconnect from session;
Alter database switch logfile; Ensure archive log shipping for log_archive_dest_2 is going fine; Select status,error from v$archive_dest where dest_id=2; Change tnsnames.ora entry on all servers to swap the connect strings ( primdb as standdb & standdb as primdb) To change the role again as Primary follow the same steps as mentioned above
To change the role again as standby follow the same steps as mentioned above
primedb_roughwork_ implementation.txt
standdb_roughwork_ implementation.txt
Don’t learn Oracle !
Live with Oracle ! With Cheers
Palaniyappan.T Senior Oracle Database Administrator Hewlett Packard Globalsoft Pvt. Ltd.,
[email protected]
