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RHEL6/CentOS6搭建Oracle Data Guard
一、工作原理
Oracle Data Guard是甲骨文推出的一种高可用性数据库方案,Data Guard确保企业数据的高可用性,数据保护和灾难恢复,Data Gurad 通过冗余数据来提供数据保护,通过日志同步机制保证冗余数据和主数之前的同步,这种同步可以是实时,延时,同步,异步多种形式。在Data Gurad环境中,至少有两个数据库,一个处于Open状态对外提供服务,这个数据库叫作Primary Database。第二个处于恢复状态,叫作Standby Database。运行时primary Database对外提供服务,用户在Primary Database上进行操作,操作被记录在联机日志和归档日志中,这些日志通过网络传递给Standby Database。这个日志会在Standby Database上重演,从而实现Primary Database和Standby Database的数据同步。
Data Guard 允许定义3种数据保护模式,分别是最大保护(Maximum Protection),最大可用(Maximum Availability)和最大性能(Maximum Performance)。
1.最大保护(Maximum Protection)
这种模式主备库之间数据是同步的。即主库提交的同时,备库会做相应的恢复。最大限度的保证了数据完整性。不允许数据的丢失。如果主备库之间网络,或者备库出现问题会直接影响主库操作。导致主库宕机。
2.最高可用性(Maximum availability)
这种模式和\”最大保护\”基本上差不多。正常情况下,主备库之间是同步的。当网络或者备库出现问题时,不会影响到主库的宕机,主库会自动转换库\”最大性能\”模式,等待备库可用时,将归档传输到备库做恢复。可以把这种模式理解为\”最大保护\”和\”最大性能\”两种模式的中间体。
3.最高性能(Maximum performance)
这种模式保证主库性能最大化,主备库之间数据是异步传输的。即,主库日志归档以后才会传输到备用库,在备库上使用归档日志文件做恢复操作。
二、搭建环境
名称 | 主库 | 备库 |
---|---|---|
主机名 | primary | standby |
standby | RHEL6.6 | RHEL6.6 |
IP | 192.168.3.176 | 192.168.3.177 |
ORACLE_BASE | /home/app/oracle | /home/app/oracle |
ORACLE_HOME | $ORACLE_BASE/product/11.2.0/dbhome_1 | $ORACLE_BASE/product/11.2.0/dbhome_1 |
ORACLE_SID | orcl | orcl |
归档模式 | 是 | 否 |
数据库版本 | Oracle 11.2.0.1.0 | Oracle 11.2.0.1.0 |
数据库安装 | 软件、监听、建库(netca、dbca) | 软件、监听、不建库 |
首先设置主备服务器时间同步参考:Linux修改时间方法如下
1.配置时间同步
#同步时间ntpdate ntp.aliyun.com
2.切换图形模式
如果没有图形界面的,配置yum源
#清楚yum仓库缓存 yum makecacheyum clean all#列出可用yum仓库yum repolist#列出程序组yum grouplist#安装图形化程序组yum -y groupinstall \"Server with GUI\"#启动图形界面startx#REHL7以下修改配置文件,以下为REHL7修改命令#查看当前运行模式systemctl get-default#设置当前运行模式systemctl set-default graphical.target#删除当前运行模式rm /etc/systemd/system/default.target#默认级别转换为3(文本模式):ln -sf /lib/systemd/system/multi-user.target /etc/systemd/system/default.target#或者默认级别转换为5(图形模式):ln -sf /lib/systemd/system/graphical.target /etc/systemd/system/default.target#重启:Reboot
3.主备数据库安装
省略
三、主库配置
1.开启归档模式
SQL> archive log list;SQL> shutdown immediate;SQL> startup mount;SQL> alter database archivelog;SQL> alter database open;SQL> archive log list;SQL> alter database force logging;SQL> select name,log_mode,force_logging from v$database;
2.创建standby redolog日志组
查看当前线程与日志组的对应关系及日志组的大小:
SQL> select thread#,group#,bytes/1024/1024 from v$log;
如上,这里有三组redo log,所以至少需要创建4组Standby redo log,大小均为50M:
SQL> alter database add standby logfile group 4(\'/home/app/oracle/oradata/orcl/standbyredo01.log\') size 50m;SQL> alter database add standby logfile group 5(\'/home/app/oracle/oradata/orcl/standbyredo02.log\') size 50m;SQL> alter database add standby logfile group 6(\'/home/app/oracle/oradata/orcl/standbyredo03.log\') size 50m;SQL> alter database add standby logfile group 7(\'/home/app/oracle/oradata/orcl/standbyredo04.log\') size 50m;
若要删除组:
SQL> alter database drop standby logfile group x;
查看standy日志组的信息:
SQL> select group#,sequence#,status, bytes/1024/1024 from v$standby_log;
3.创建主库密码文件
su - oracleorapwd file=$ORACLE_HOME/dbs/orapw$ORACLE_SID password=oracle force=y
4.配置spfile文件
查看spfile文件路径:
SQL> show parameter spfile;
用spfile创建一个pfile,用于修改:
SQL> create pfile=\'/tmp/initorcl.ora\' from spfile;
修改pfile文件
vim /tmp/initorcl.oraorcl.__db_cache_size=327155712orcl.__java_pool_size=4194304orcl.__large_pool_size=4194304orcl.__oracle_base=\'/home/app/oracle\'#ORACLE_BASE set from environmentorcl.__pga_aggregate_target=335544320orcl.__sga_target=499122176orcl.__shared_io_pool_size=0orcl.__shared_pool_size=155189248orcl.__streams_pool_size=0*.audit_file_dest=\'/home/app/oracle/admin/orcl/adump\'*.audit_trail=\'db\'*.compatible=\'11.2.0.0.0\'*.control_files=\'/home/app/oracle/oradata/orcl/control01.ctl\',\'/home/app/oracle/flash_recovery_area/orcl/control02.ctl\'*.db_block_size=8192*.db_domain=\'\'*.db_name=\'orcl\'*.db_recovery_file_dest=\'/home/app/oracle/flash_recovery_area\'*.db_recovery_file_dest_size=4070572032*.diagnostic_dest=\'/home/app/oracle\'*.dispatchers=\'(PROTOCOL=TCP) (SERVICE=orclXDB)\'*.log_archive_format=\'%t_%s_%r.dbf\'*.memory_target=833617920*.open_cursors=300*.processes=150*.remote_login_passwordfile=\'EXCLUSIVE\'*.undo_tablespace=\'UNDOTBS1\'#添加以下内容*.db_unique_name=\'orclpr\'*.fal_client=\'orclpr\'*.fal_server=\'orcldg\'*.standby_file_management=\'AUTO\'*.log_archive_config=\'DG_CONFIG=(orclpr,orcldg)\'*.log_archive_dest_1=\'location=/home/app/oracle/oradata/orcl/archivelog\'*.log_archive_dest_2=\'SERVICE=orcldg LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=orcldg\'*.log_archive_dest_state_1=\'ENABLE\'*.log_archive_dest_state_2=\'ENABLE\'
复制pfile文件到spfile:
SQL> shutdown immediate;SQL> create spfile from pfile=\'/tmp/initorcl.ora\';SQL> startup;
5.修改监听文件,添加静态监听
vim $ORACLE_HOME/network/admin/listener.oraLISTENER =(DESCRIPTION_LIST =(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = primary)(PORT = 1521))(ADDRESS = (PROTOCOL = IPC)(KEY = orcl))))LISTENER =(DESCRIPTION_LIST =(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.3.176)(PORT = 1521))(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))))SID_LIST_LISTENER =(SID_LIST =(SID_DESC =(GLOBAL_DBNAME = orcl)(ORACLE_HOME = /home/app/oracle/product/11.2.0/dbhome_1)(SID_NAME = orcl)))ADR_BASE_LISTENER = /home/app/oracleSAVE_CONFIG_ON_STOP_LISTENER = ON
重启监听服务:
SQL> lsnrctl stopSQL> lsnrctl start
6.编辑网络服务名配置文件tnsnames.ora
vim $ORACLE_HOME/network/admin/tnsnames.oraorclpr =(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.3.176)(PORT = 1521))(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = orcl)))orcldg =(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.3.177)(PORT = 1521))(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = orcl)))
tnsping测试:
[oracle@primary ~]$ sqlplus sys/oracle@orclpr as sysdba[oracle@primary ~]$ sqlplus sys/oracle@orcldg as sysdba[oracle@primary ~]$ tnsping orcldg[oracle@primary ~]$ tnsping orclpr
四、备库配置
1.将主库中的密码文件、pfile文件、监听文件复制到备库中
cd /home/app/oracle/product/11.2.0/dbhome_1/dbsscp orapworcl 192.168.3.177:/home/app/oracle/product/11.2.0/dbhome_1/dbs/scp /tmp/initorcl.ora 192.168.3.177:/tmp/cd /home/app/oracle/product/11.2.0/dbhome_1/network/adminscp listener.ora 192.168.3.177:/home/app/oracle/product/11.2.0/dbhome_1/network/admin/scp tnsnames.ora 192.168.3.177:/home/app/oracle/product/11.2.0/dbhome_1/network/admin/
2.配置spfile文件
修改pfile文件:
vim /tmp/initorcl.oraorcl.__db_cache_size=327155712orcl.__java_pool_size=4194304orcl.__large_pool_size=4194304orcl.__oracle_base=\'/home/app/oracle\'#ORACLE_BASE set from environmentorcl.__pga_aggregate_target=335544320orcl.__sga_target=499122176orcl.__shared_io_pool_size=0orcl.__shared_pool_size=155189248orcl.__streams_pool_size=0*.audit_file_dest=\'/home/app/oracle/admin/orcl/adump\'*.audit_trail=\'db\'*.compatible=\'11.2.0.0.0\'*.control_files=\'/home/app/oracle/oradata/orcl/control01.ctl\',\'/home/app/oracle/flash_recovery_area/orcl/control02.ctl\'*.db_block_size=8192*.db_domain=\'\'*.db_name=\'orcl\'*.db_recovery_file_dest=\'/home/app/oracle/flash_recovery_area\'*.db_recovery_file_dest_size=4070572032*.diagnostic_dest=\'/home/app/oracle\'*.dispatchers=\'(PROTOCOL=TCP) (SERVICE=orclXDB)\'*.log_archive_format=\'%t_%s_%r.dbf\'*.memory_target=833617920*.open_cursors=300*.processes=150*.remote_login_passwordfile=\'EXCLUSIVE\'*.undo_tablespace=\'UNDOTBS1\'#添加以下内容*.db_unique_name=\'orcldg\'*.fal_client=\'orcldg\'*.fal_server=\'orclpr\'*.standby_file_management=\'AUTO\'*.log_archive_config=\'DG_CONFIG=(orclpr,orcldg)\'*.log_archive_dest_1=\'location=/home/app/oracle/oradata/orcl/archivelog\'*.log_archive_dest_2=\'SERVICE=orclpr LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=orclpr\'*.log_archive_dest_state_1=\'ENABLE\'*.log_archive_dest_state_2=\'ENABLE\'
复制pfile文件到spfile:
SQL> create spfile from pfile=\'/tmp/initorcl.ora\';
3.修改监听文件
vim $ORACLE_HOME/network/admin/listener.oraSID_LIST_LISTENER =(SID_LIST =(SID_DESC =(GLOBAL_DBNAME = orcl)(ORACLE_HOME = /home/app/oracle/product/11.2.0/dbhome_1)(SID_NAME = orcl)))LISTENER =(DESCRIPTION_LIST =(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.3.177)(PORT = 1521))(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))))ADR_BASE_LISTENER = /home/app/oracle
编辑网络服务名配置文件tnsnames.ora
vim $ORACLE_HOME/network/admin/tnsnames.oraorcldg =(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.3.177)(PORT = 1521))(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = orcl)))orclpr =(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.3.176)(PORT = 1521))(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = orcl)))
重启监听:
SQL> lsnrctl stopSQL> lsnrctl start
4.tnsping测试
[oracle@standby ~]$ tnsping orclpr[oracle@standby ~]$ tnsping orcldg
5.手工创建所需的目录
su - oraclemkdir -p /home/app/oracle/admin/orcl/adumpmkdir -p /home/app/oracle/admin/orcl/dpdumpmkdir -p /home/app/oracle/admin/orcl/pfilemkdir -p /home/app/oracle/oradata/orclmkdir -p /home/app/oracle/flash_recovery_area/orclmkdir -p /home/app/oracle/oradata/orcl/archivelog
6.启动备库到nomount
SQL> shutdown immediate;SQL> startup nomount;
五、数据恢复
1.配置参数检查
SQL> select status from v$instance;SQL> show parameter db_unique_name;
primary:orclpr
standby:orcldg
SQL> show parameter compatible;SQL> show parameter log_archive_config;SQL> show parameter log_archive_dest_1;SQL> show parameter log_archive_dest_state_2;SQL> show parameter db_file_name_convert;--SQL> alter system set db_file_name_convert=\'/home/app/oracle/oradata/orcl\',\'/home/app/oracle/oradata/orcl\' scope=spfile;SQL> show parameter log_file_name_convert;--SQL> alter system set log_file_name_convert=\'/home/app/oracle/oradata/orcl\',\'/home/app/oracle/oradata/orcl\' scope=spfile;SQL> show parameter standby;SQL> show parameter log_archive_format;--SQL> alter system set LOG_ARCHIVE_FORMAT=\'ARC_%T_%S_%R.arc\' scope=both;SQL> set pagesize 100;SQL> set linesize 120;SQL> shutdown immediate;SQL> startup mount;SQL> alter database archivelog;SQL> alter database open;SQL> archive log list;
2.利用RMAN在主库上恢复备库
rman target sys/oracle@orclpr auxiliary sys/oracle@orcldgduplicate target database for standby from active database nofilenamecheck;#备注:rman target sys/oracle@orclpr auxiliary sys/oracle@orcldg nocatalog#恢复过程如下:[oracle@oracle11gstandby admin]$ rman target sys/oracle@orclpr auxiliary sys/oracle@orcldgduplicate target database for standby from active database nofilenamecheck;
3.登陆备库并查看数据库当前状态
[oracle@standby ~]$ sqlplus / as sysdba
SQL> select status from v$instance;
RMAN恢复完直接就是mount状态。
4.备库启动日志应用
SQL> alter database recover managed standby database using current logfile disconnect from session;SQL> select sequence#,applied from v$archived_log order by 1;
5.分别查看主库和备库的归档序列号是否一致
先在主库手动切换一下日志再查看
SQL> alter system switch logfile;SQL> archive log list;
再在备库上查看:
SQL> archive log list;
6.查看备库中各文件如下
[oracle@standby orcl]$ ll[oracle@standby archivelog]$ ll
到此,dataguard已部署完成,可以测试是否成功!
建议用scott用户测试,insert、delete、update、select
六、自动启动
1.Oracle DG物理备库在数据库重启后,不能自动对日志进行应用,可通过以下触发器来让数据库应用日志。
CREATE OR REPLACE TRIGGER STANDBY_APPLY_LOGAFTER STARTUP ON DATABASEBEGINDECLAREDATABASE_ROLE VARCHAR(20);BEGINSELECT DATABASE_ROLE INTO DATABASE_ROLE FROM V$DATABASE;IF DATABASE_ROLE = \'PHYSICAL STANDBY\' THENEXECUTE IMMEDIATE \'ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE DISCONNECT FROM SESSION\';ELSEDBMS_OUTPUT.PUT_LINE(DATABASE_ROLE);END IF;END;END STANDBY_APPLY_LOG;
七、主备切换
1.检查主备的环境
SQL> select name,switchover_status,database_role from v$database;
验证备库是否有gap
SQL> select t.status,t.gap_status from v$archive_dest_status t where t.dest_id=\'2\';
2.在主库上执行切换命令(primary节点)
SQL> alter database commit to switchover to physical standby;--备库启动日志应用SQL> alter database commit to switchover to physical standby with session shutdown;SQL> shutdown immediate;SQL> startup mount;SQL> select name,switchover_status,database_role from v$database;
查看目前primary角色的状态
3.在备库上执行(standby节点)
SQL> select name,switchover_status,database_role from v$database;--查看standby备库角色的状态SQL> alter database commit to switchover to primary with session shutdown;--将备库的角色修改为primarySQL> select name,switchover_status,database_role from v$database;
打开数据库
SQL> alter database open;--修改以前主库为日志应用--备库启动日志应用SQL> alter database recover managed standby database using current logfile disconnect from session;
4.测试主备节点是否切换成功
测试省略
如果是正式库,数据库运行时间长,切换的时间会很长。主备库:
SQL> alter system flush buffer_cache;SQL> alter system checkpoint;SQL> shutdown immediate;
八、参考说明
1.参考文档
参考文档是英文的,可以翻译成中文阅读,有时候翻译的不太准确…
http://docs.oracle.com/cd/B19306_01/server.102/b14239/create_ps.htm
2.常用命令
--Primary:SELECT T.NAME,T.OPEN_MODE,T.DATABASE_ROLE,T.PROTECTION_MODE,T.PROTECTION_LEVEL FROM V$DATABASE T;--Standby:SELECT T.NAME,T.OPEN_MODE,T.DATABASE_ROLE,T.PROTECTION_MODE,T.PROTECTION_LEVEL FROM V$DATABASE T;
备注:如果OPEN_MODE=WITH APPLY在备库上执行
SQL> alter database recover managed standby database using current logfile disconnect from session;SQL> SELECT * FROM V$MANAGED_STANDBY;
3.启动说明
关闭数据库:主库–>备库
启动数据库:备库–>主库