oracle DG 簡介

　

 

 

Oracle DataGuard；簡稱DG。是由一個Primary Database（主庫）和一個或者多個Standby Database（備庫）組成。對Oracle來說；本身不能提高性能。通過數據冗余來保護數據。由Primary Database對外提供服務；用戶操作在Primary Database上操作；其操作的數據庫Redo Log或者Archive log通過網絡傳輸到Standby Database。Standby Database在重做這些日志。從而實現Primary Database和Standby Database數據同步。

架構圖如下：

Oracle DataGuard中的Standby庫有兩種：物理Standby和邏輯Standby。

• 邏輯Standby接收后將其轉換成SQL語句，在Standby數據庫上執行SQL語句實現同步，這種方式叫SQL Apply。
• 物理Standby接收完Primary數據庫生成的REDO數據后，以介質恢復的方式實現同步，這種方式也叫Redo Apply。

2|0二. Oracle DataGuard搭建

　　安裝規划：

IP	ROLE
192.168.1.235	Primary
192.168.1.221	Standby

2|12.1. 主庫設置歸檔模式

alter database archivelog;

2|22.2. 主庫設置Force Logging模式

alter database force logging;

2|32.3. 備庫創建相應的dump文件夾

# 在主庫查詢對應的dump目錄 select name, value from v$parameter where name in ('audit_file_dest', 'background_dump_dest', 'control_files', 'core_dump_dest', 'user_dump_dest', 'db_recovery_file_dest' ) ORDER BY name ASC; # 備庫用oracle用戶執行創建目錄 mkdir -p $value

2|42.4. 配置Standby Redologs

　　對於模式中最大保護和最高可用性；采用是 LGWR 模式傳送 Redo 日志；需要為 Standby庫配置 Standby Redologs。Standby Redologs 和 ONline Redologs 文件大小是相同的。比 ONline Redologs 個數要 +1 。

# 查看redologs日志信息 SQL> select group#,type,member from v$logfile; GROUP# TYPE MEMBER ------ ---------- -------------------------------------------------- 1 ONLINE /u01/app/oradata/ora235/redo01.log 2 ONLINE /u01/app/oradata/ora235/redo02.log 3 ONLINE /u01/app/oradata/ora235/redo03.log SQL> select group#,bytes from v$log; GROUP# BYTES ------ ---------- 1 52428800 2 52428800 3 52428800 # 添加Standby Redologs；添加如下： ALTER DATABASE ADD STANDBY LOGFILE GROUP 4('/u01/app/oradata/ora235/stdred001.log') SIZE 50 M; ALTER DATABASE ADD STANDBY LOGFILE GROUP 5('/u01/app/oradata/ora235/stdred002.log') SIZE 50 M; ALTER DATABASE ADD STANDBY LOGFILE GROUP 6('/u01/app/oradata/ora235/stdred003.log') SIZE 50 M; ALTER DATABASE ADD STANDBY LOGFILE GROUP 7('/u01/app/oradata/ora235/stdred004.log') SIZE 50 M;

2|52.5. 創建實例密鑰文件

• 主庫生成密鑰文件

orapwd FILE=/u01/app/oracle/dbs/orapwora235 password=li0924 entries=5;

• 將密鑰文件傳輸到備庫

scp /u01/app/oracle/dbs/orapwora235 oracle@192.168.1.221:/u01/app/oracle/dbs

2|62.6. 創建參數文件

　　本文采用 Primary 庫和 Standby 庫采用相同路徑；所以僅設置必要的參數。

• 主庫通過spfile生成pfile文件

create pfile from spfile;

• 添加Primary端的pfile內容如下

*.DB_UNIQUE_NAME=db_primary *.LOG_ARCHIVE_CONFIG='DG_CONFIG=(db_primary,db_standby)' *.LOG_ARCHIVE_DEST_2='SERVICE=tns_standby LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=db_standby' *.LOG_ARCHIVE_DEST_STATE_2=DEFER *.LOG_FILE_NAME_CONVERT ='/u01/app/oradata/ora235/','/u01/app/oradata/ora235/' *.FAL_SERVER=tns_standby *.FAL_CLIENT=tns_primary *.STANDBY_FILE_MANAGEMENT=AUTO

• Primary重新啟動

primary>create spfile from pfile; File created. primary>startup ORACLE instance started. Total System Global Area 780824576 bytes Fixed Size 2257312 bytes Variable Size 511708768 bytes Database Buffers 264241152 bytes Redo Buffers 2617344 bytes Database mounted. Database opened.

• 復制參數文件到Standby庫

scp /u01/app/oracle/dbs/initora235.ora oracle@192.168.1.221:/u01/app/oracle/dbs

• 添加Standby端的pfile內容如下

*.DB_UNIQUE_NAME=db_standby *.LOG_ARCHIVE_CONFIG='DG_CONFIG=(db_primary,db_standby)' *.LOG_ARCHIVE_DEST_2='SERVICE=tns_primary LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=db_primary' *.LOG_FILE_NAME_CONVERT ='/u01/app/oradata/ora235/','/u01/app/oradata/ora235/' *.LOG_ARCHIVE_DEST_STATE_2=ENABLE *.FAL_SERVER=tns_primary *.FAL_CLIENT=tns_standby *.STANDBY_FILE_MANAGEMENT=AUTO

• 將Standby端啟動到nomount狀態

[oracle@oracle221 ~]$ sqlplus / as sysdba SQL*Plus: Release 11.2.0.4.0 Production on Thu Aug 9 22:56:49 2018 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to an idle instance. SQL> startup nomount; ORACLE instance started. Total System Global Area 780824576 bytes Fixed Size 2257312 bytes Variable Size 511708768 bytes Database Buffers 264241152 bytes Redo Buffers 2617344 bytes

2|72.7 配置主備庫的監聽文件和網絡文件

• 設置Primary庫和Standby庫的service_name

SQL> show parameter service_name; NAME TYPE VALUE ------------------------------------ ----------- --------------- service_names string lottu SQL> alter system set service_names='db_primary' scope=both; System altered. SQL> show parameter service_name; NAME TYPE VALUE ------------------------------------ ----------- ---------------- service_names string db_primary

• 備庫的service_name設置為db_standby；需要到參數文件修改。

*.service_names='db_standby'

• Primary庫配置listener.ora

LISTENER = (DESCRIPTION_LIST = (DESCRIPTION = (ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.235)(PORT = 1521)(IP = FIRST))) (ADDRESS_LIST = (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC)) ) ) ) SID_LIST_LISTENER = (SID_LIST = (SID_DESC = (SID_NAME = ora235) (GLOBAL_DBNAME = db_primary) (ORACLE_HOME =/u01/app/oracle) ) )

• Standby庫配置listener.ora

LISTENER = (DESCRIPTION_LIST = (DESCRIPTION = (ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.221)(PORT = 1521)(IP = FIRST))) (ADDRESS_LIST = (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC)) ) ) ) SID_LIST_LISTENER = (SID_LIST = (SID_DESC = (SID_NAME = ora235) (GLOBAL_DBNAME = db_standby) (ORACLE_HOME =/u01/app/oracle) ) )

• Primary庫和Standby庫設置tnsname.ora

tns_primary= (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.235)(PORT = 1521)) (CONNECT_DATA = (SERVICE_NAME = db_primary) ) (HS = OK) ) tns_standby= (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.221)(PORT = 1521)) (CONNECT_DATA = (SERVICE_NAME = db_standby) ) (HS = OK) )

　　重啟監聽lsnrctl restart

2|82.8. 克隆Standby庫

在Primary庫執行

[oracle@oracle235 admin]$ rman target sys/li0924@tns_primary auxiliary sys/li0924@tns_standby Recovery Manager: Release 11.2.0.4.0 - Production on Thu Aug 9 23:56:46 2018 Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved. connected to target database: ORA235 (DBID=2047494122) connected to auxiliary database: ORA235 (not mounted) RMAN> DUPLICATE TARGET DATABASE FOR STANDBY FROM ACTIVE DATABASE DORECOVER NOFILENAMECHECK; Starting Duplicate Db at 09-AUG-18 using target database control file instead of recovery catalog allocated channel: ORA_AUX_DISK_1 channel ORA_AUX_DISK_1: SID=20 device type=DISK contents of Memory Script: { backup as copy reuse targetfile '/u01/app/oracle/dbs/orapwora235' auxiliary format '/u01/app/oracle/dbs/orapwora235' ; } executing Memory Script Starting backup at 09-AUG-18 allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=26 device type=DISK Finished backup at 09-AUG-18 contents of Memory Script: { backup as copy current controlfile for standby auxiliary format '/u01/app/oradata/ora235/control01.ctl'; restore clone controlfile to '/u01/app/oradata/ora235/control02.ctl' from '/u01/app/oradata/ora235/control01.ctl'; } executing Memory Script Starting backup at 09-AUG-18 using channel ORA_DISK_1 channel ORA_DISK_1: starting datafile copy copying standby control file output file name=/u01/app/oracle/dbs/snapcf_ora235.f tag=TAG20180809T235658 RECID=4 STAMP=983750219 channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:01 Finished backup at 09-AUG-18 Starting restore at 09-AUG-18 using channel ORA_AUX_DISK_1 channel ORA_AUX_DISK_1: copied control file copy Finished restore at 09-AUG-18 contents of Memory Script: { sql clone 'alter database mount standby database'; } executing Memory Script sql statement: alter database mount standby database contents of Memory Script: { set newname for tempfile 1 to "/u01/app/oradata/ora235/temp01.dbf"; switch clone tempfile all; set newname for datafile 1 to "/u01/app/oradata/ora235/system01.dbf"; set newname for datafile 2 to "/u01/app/oradata/ora235/sysaux01.dbf"; set newname for datafile 3 to "/u01/app/oradata/ora235/undotbs01.dbf"; set newname for datafile 4 to "/u01/app/oradata/ora235/users01.dbf"; set newname for datafile 5 to "/data/oracle/data/lottu01.dbf"; backup as copy reuse datafile 1 auxiliary format "/u01/app/oradata/ora235/system01.dbf" datafile 2 auxiliary format "/u01/app/oradata/ora235/sysaux01.dbf" datafile 3 auxiliary format "/u01/app/oradata/ora235/undotbs01.dbf" datafile 4 auxiliary format "/u01/app/oradata/ora235/users01.dbf" datafile 5 auxiliary format "/data/oracle/data/lottu01.dbf" ; sql 'alter system archive log current'; } executing Memory Script executing command: SET NEWNAME renamed tempfile 1 to /u01/app/oradata/ora235/temp01.dbf in control file executing command: SET NEWNAME executing command: SET NEWNAME executing command: SET NEWNAME executing command: SET NEWNAME executing command: SET NEWNAME Starting backup at 09-AUG-18 using channel ORA_DISK_1 channel ORA_DISK_1: starting datafile copy input datafile file number=00005 name=/data/oracle/data/lottu01.dbf output file name=/data/oracle/data/lottu01.dbf tag=TAG20180809T235706 channel ORA_DISK_1: datafile copy complete, elapsed time: 00:01:45 channel ORA_DISK_1: starting datafile copy input datafile file number=00001 name=/u01/app/oradata/ora235/system01.dbf output file name=/u01/app/oradata/ora235/system01.dbf tag=TAG20180809T235706 channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:35 channel ORA_DISK_1: starting datafile copy input datafile file number=00002 name=/u01/app/oradata/ora235/sysaux01.dbf output file name=/u01/app/oradata/ora235/sysaux01.dbf tag=TAG20180809T235706 channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:35 channel ORA_DISK_1: starting datafile copy input datafile file number=00003 name=/u01/app/oradata/ora235/undotbs01.dbf output file name=/u01/app/oradata/ora235/undotbs01.dbf tag=TAG20180809T235706 channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:25 channel ORA_DISK_1: starting datafile copy input datafile file number=00004 name=/u01/app/oradata/ora235/users01.dbf output file name=/u01/app/oradata/ora235/users01.dbf tag=TAG20180809T235706 channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:01 Finished backup at 10-AUG-18 sql statement: alter system archive log current contents of Memory Script: { backup as copy reuse archivelog like "/data/arch/1_3_983660602.dbf" auxiliary format "/data/arch/1_3_983660602.dbf" ; catalog clone archivelog "/data/arch/1_3_983660602.dbf"; switch clone datafile all; } executing Memory Script Starting backup at 10-AUG-18 using channel ORA_DISK_1 channel ORA_DISK_1: starting archived log copy input archived log thread=1 sequence=3 RECID=19 STAMP=983750428 output file name=/data/arch/1_3_983660602.dbf RECID=0 STAMP=0 channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01 Finished backup at 10-AUG-18 cataloged archived log archived log file name=/data/arch/1_3_983660602.dbf RECID=1 STAMP=983750429 datafile 1 switched to datafile copy input datafile copy RECID=4 STAMP=983750429 file name=/u01/app/oradata/ora235/system01.dbf datafile 2 switched to datafile copy input datafile copy RECID=5 STAMP=983750429 file name=/u01/app/oradata/ora235/sysaux01.dbf datafile 3 switched to datafile copy input datafile copy RECID=6 STAMP=983750429 file name=/u01/app/oradata/ora235/undotbs01.dbf datafile 4 switched to datafile copy input datafile copy RECID=7 STAMP=983750429 file name=/u01/app/oradata/ora235/users01.dbf datafile 5 switched to datafile copy input datafile copy RECID=8 STAMP=983750429 file name=/data/oracle/data/lottu01.dbf contents of Memory Script: { set until scn 955597; recover standby clone database delete archivelog ; } executing Memory Script executing command: SET until clause Starting recover at 10-AUG-18 using channel ORA_AUX_DISK_1 starting media recovery archived log for thread 1 with sequence 3 is already on disk as file /data/arch/1_3_983660602.dbf archived log file name=/data/arch/1_3_983660602.dbf thread=1 sequence=3 media recovery complete, elapsed time: 00:00:00 Finished recover at 10-AUG-18 Finished Duplicate Db at 10-AUG-18

2|92.9. 啟用日志傳送

在 Primary 端啟動日志傳送

alter system set LOG_ARCHIVE_DEST_STATE_2=ENABLE;

2|102.10. 啟用實時應用redo

　　在 Primary Database 產生的 Redo 日志；傳送到 Standby Database；是通過 LGWR 或者 ARCH 進程完成。這個很好理解。默認情況下是由 ARCH 進程。有參數 *.LOG_ARCHIVE_DEST_2 控制的。使用 ARCH 進程； Primary Database 和 Standby Database 存在數據延遲。若 Primary Database 出現異常；容易造成部分數據丟失。為了避免數據丟失，必須要使用 LGWR 進程，需要用到 Standby Redolog。而LGWR 又分SYNC（同步）和ASYNC（異步）兩種方式。

• SYNC方式：對網絡要求比較高；必須等待寫入本地日志文件操作和通過LNSn進程的網絡傳送都成功，Primary Database 上的事務才能提交成功。使用LGWR SYNC方式時，可以同時使用NET_TIMEOUT參數，這個參數單位是秒，代表如果多長時間內網絡發送沒有響應，LGWR 進程會拋出錯誤。因此對 Primary Database 性能有影響。

*.LOG_ARCHIVE_DEST_2='SERVICE=tns_standby LGWR SYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=db_standby NET_TIMEOUT = 30'

• ASYNC方式：采用異步方式；Primary Database 上的事務提交跟日志是否已經傳送沒有影響。

*.LOG_ARCHIVE_DEST_2='SERVICE=tns_standby LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=db_standby'

1. 在 Primary Database上執行；

alter system set log_archive_dest_2='SERVICE=tns_standby LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=db_standby' scope=both;

2. 在Standby Database上執行；

alter system set log_archive_dest_2='SERVICE=tns_primary LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=db_primary' scope=both;

3. Standby Database啟動實時應用redo

alter database recover managed standby database using current logfile ;

4. 驗證結果

# 在Primary Database 上創建表t_lottu02 SQL> set SQLPROMPT Primary> Primary>conn lottu/li0924 Connected. Primary>create table t_lottu02 as select level id,'lottu' name from dual connect by level <= 3; Table created. # 在Standby Database上查看 SQL> set SQLPROMPT StandBy> StandBy>conn lottu/li0924 Connected. StandBy>select * from t_lottu02; ID NAME ---------- ----- 1 lottu 2 lottu 3 lottu

 

原文：https://www.cnblogs.com/lottu/p/9542053.html

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