Oracel DG安装指南
1.文档介绍
本实施方案主要对Oracle DataGuard实施部署作相应的说明。以便实施人员能根据当前业务特点，规划、建设符合高可用、高可靠的数据库集群系统。具体由Oracle DG环境拓扑、Oracle单机数据库规划部分构成！
2 .Oracle Data Guard 介绍
2.1 Data Guard环境拓展
2.2 Data Guard特点
数据库服务器采用DATAGUARD灾备模式，可以满足对可用性有特殊需求的应用，具备以下特点：
1、 需要冗余的服务器设备。该模式需要有冗余的服务器硬件。硬件成本较高。
2、 需要冗余的存储设备。主机和备机都需要同样的存储空间，成本较高。
3、 安装配置比较复杂。该模式比单节点、单实例的模式配置复杂一些，需要更多的配置步骤。
4、 管理维护成本高。该模式对维护人员的要求较高，维护成本高。
5、 具备一定的容灾特性。当主机整个数据库系统不可用并短期内无法恢复时，可以把数据库系统切换到备机上，具备容灾的功能。
6、 备机可以用作只读查询。备机可以切换到只读状态供报表之类的查询操作，减轻主机的压力。
3.Oracle DataGurad单实例部署
3.1安装环境
在主机1上安装数据库软件，并建监听和实例，在主机2上安装数据库软件，并建监听，但不建实例。
| 主机1（主库） | 主机2（备库） | |
|---|---|---|
| 操作系统 | Centos7.6 64位 | Centos7.6 64位 |
| 主机名 | davyprimary | davystandbyIP |
| 地址 | 192.168.1.140 | 192.168.1.141 |
| 数据库软件版本 | oracle 11.2.0.4 | oracle 11.2.0.4 |
| ORACLE_BASE | /u01/app/oracle | /u01/app/oracle |
| ORACLE_HOME | /u01/app/oracle/product/11.2.0.4/dbhome_1 | /u01/app/oracle/product/11.2.0.4/dbhome_1 |
| ORACLE_SID | LHR11G | LHR11GS |
| 闪回区 | 开启 | |
| 归档 | 开启 |
3.2主数据库配置
3.2.1设置数据库归档
主备库均为归档模式，并且force logging
3.2.1.1查看数据库是否运行在归档模式：
-- 查看数据库是否运行在归档模式：
SYS@LHR11G> archive log list;
备注：如果数据库已经开启归档，下面的操纵可以忽略。
3.2.1.2开启数据库归档
SYS@LHR11G> shutdown immediate #关闭数据库
Database closed.
Database dismounted.
ORACLE instance shut down.
SYS@LHR11G> startup mount #启动到mount状态
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
Database mounted.
SYS@LHR11G> alter database archivelog; #开启归档
Database altered.
SYS@LHR11G> alter database open; #open数据库
Database altered.
SYS@LHR11G> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 19
Next log sequence to archive 21
Current log sequence 21
3.2.2设置数据库闪回
3.2.2.1查看是否开启闪回
SYS@LHR11G> select flashback_on from v$database;
FLASHBACK_ON
NO
备注：如果数据库已经开启flashback，那么下面步骤可忽略。如上显示，该数据库未开启flashback，可按下面方法开启。
3.2.2.2开启数据库闪回设置
[root@oracleprimary /]# mkdir -p /data/LHR11G/recoverydest #创建闪回去路径
目录
[root@oracleprimary data]# chown oracle:dba /data/LHR11G/recoverydest/
SYS@LHR11G> alter system set db_recovery_file_dest='/data/LHR11G/recoverydest'; #设置闪回路径
System altered.
SYS@LHR11G> alter system set db_recovery_file_dest_size='5G';
System altered.
SYS@LHR11G> shutdown immediate; #关闭数据库
Database closed.
Database dismounted.
ORACLE instance shut down.
SYS@LHR11G> startup mount;
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
Database mounted.
SYS@LHR11G> alter database flashback on; #开启闪回
Database altered.
SYS@LHR11G> alter database open; #open数据库
Database altered.
SYS@LHR11G> select flashback_on from v$database; #验证是否开启
FLASHBACK_ON
------------------------------------
YES
3.2.3设置数据库为强制记日志
设置force logging，修改数据库为强制记日志，这是必须的操作，主库的每一步操作都得记录到日志中去。
3.2.3.1查看数据库是否开启强制记日志：
-- 查看数据库归档模式是否强制归档:
SYS@LHR11G> select name,log_mode,force_logging from v$database;
NAME LOG_MODE FORCE_
------------------ ------------------------ ------
LHR11G ARCHIVELOG NO
备注：如果数据库已经开启force logging，那么下面步骤可忽略。如上可以看出数据库未开启，则按下面步骤执行
3.2.3.1开启强制记日志设置
SYS@LHR11G> alter database force logging; #开启force logging
Database altered.
SYS@LHR11G> select name,log_mode,force_logging from v$database; #验证
NAME LOG_MODE FORCE_
------------------ ------------------------ ------
LHR11G ARCHIVELOG YES
3.2.4 添加STANDBY 日志文件
在备库，当RFS进程接受到日志后，就将其写入Standby日志文件里，备库的Standby日志文件可以看做是主库在线日志文件的一个镜像，当主库做日志切换时，备库的Standby日志也做相应的切换，切换后的Standby日志由备库的ARCH进程归档。
Oracle规定备库的Standby日志文件大小不能小于主库在线日志文件最大的一个，一般情况下，为了管理方便，最好把所有的在线日志和Standby日志大小设为一样。
-- 通过下面语句可以查询主库在线日志的大小和组数
SYS@LHR11G> select group#,bytes/1024/1024 from v$log;
GROUP# BYTES/1024/1024
---------- ---------------
1 50
2 50
3 50
-- 通过下面的语句可以查询备库Standby日志的大小和组数：
SYS@LHR11G> select group#,bytes/1024/1024 from v$standby_log;
no rows selected
-- 创建standby logfile
[root@oracleprimary data]# mkdir -p /data/LHR11G/onlinelog
[root@oracleprimary data]# chown oracle:dba /data/LHR11G/onlinelog
SYS@LHR11G> alter database add standby logfile group 11 '/data/LHR11G/onlinelog/redo11_stb01.log' size 50M;
SYS@LHR11G> alter database add standby logfile group 11 '/data/LHR11G/onlinelog/redo11_stb01.log' size 50M;
Database altered.
SYS@LHR11G> alter database add standby logfile group 12 '/data/LHR11G/onlinelog/redo12_stb01.log'size 50M;
Database altered.
SYS@LHR11G> alter database add standby logfile group 13 '/data/LHR11G/onlinelog/redo13_stb01.log'size 50M;
Database altered.
SYS@LHR11G> alter database add standby logfile group 14 '/data/LHR11G/onlinelog/redo14_stb01.log'size 50M;
Database altered.
SYS@LHR11G> select group#,bytes/1024/1024 from v$standby_log;
GROUP# BYTES/1024/1024
---------- ---------------
11 50
12 50
13 50
14 50
3.2.5 主库的参数设置
-- 10g的DATA GUARD的一个主要特点就是引入了log_archive_config参数，如果缺少这个参数，可能会导致归档路径被禁用。
SYS@LHR11G> alter system set log_archive_config="dg_config=(LHR11G,LHR11GS)" scope=both;
System altered.
-- 设置归档路径
[root@oracleprimary data]# mkdir -p /data/LHR11G/archivelog
[root@oracleprimary data]# chown oracle:dba /data/LHR11G/archivelog
-- 设置归档路径1
SYS@LHR11G> alter system set log_archive_dest_1='location=/data/LHR11G/archivelog/ valid_for=(all_logfiles,all_roles) db_unique_name=LHR11G';
System altered.
SYS@LHR11G> alter system set log_archive_dest_state_1="enable";
System altered.
-- 设置归档路径2 远程归档
-- 远程目标的Oracle Net别名，由关键字SERVICE指定。指定的服务名通过使用本地的tnsnames.ora文件进行解析，以标识远程数据库。
SYS@LHR11G> alter system set log_archive_dest_2="service=LHR11GS lgwr async valid_for=(online_logfile,primary_role) db_unique_name=LHR11GS" scope=both;
System altered.
SYS@LHR11G> alter system set log_archive_dest_state_2="enable";
System altered.
-- 主数据库和备用数据库的数据文件转换目录映射
SYS@LHR11G> alter system set db_file_name_convert="/data/LHR11GS/datafile","/data/LHR11G/datafile" scope=spfile;
System altered.
-- 指明主数据库和备用数据库的log文件转换目录映射。
SYS@LHR11G> alter system set log_file_name_convert="/data/LHR11GS/onlinelog","/data/LHR11G/onlinelog" scope=spfile;
-- 方便switchover或failover时primary库转变为standby角色
System altered.
-- FAL_SERVER指定一个Oracle Net service name,standby数据库使用这个参数连接到FAL server,这个参数适用于standby站点。
-- 比如,FAL_SERVER = PrimaryDB,此处PrimaryDB是一个TNS name,指向primary库
SYS@LHR11G> alter system set fal_server=LHR11GS scope=both;
System altered.
-- FAL_CLIENT指定一个FAL客户端的名字，以便FAL Server可以引用standby库，这也是一个TNS name，primary库必须适当配置此TNS name指向stanby库。
-- 这个参数也是在standby库端设置。比如，FAL_CLIENT = StandbyDB,StandbyDB是standby库的TNS name。
SYS@LHR11G> alter system set fal_client=LHR11G scope=both;
System altered.
SYS@LHR11G> alter system set standby_file_management=auto scope=both;
System altered.
FAL_CLIENT和FAL_SERVER是配置dataguard用到的两个参数,FAL指获取归档日志(Fetch Archived Log)
在一定的条件下，或者因为网络失败，或者因为资源紧张，会在primary和standby之间产生裂隙，也就是有些归档日志没有及时的传输并应用到standby库。因为MRP(managed recovery process)/LSP(logical standby process)没有与primary直接通讯的能力来获取丢失的归档日志。因此这些gaps通过FAL客户和服务器来解决，由初始化参数定义FAL_CLIENT和FAL_SERVER。
FAL_SERVER指定一个Oracle Net service name,standby数据库使用这个参数连接到FAL server,这个参数适用于standby站点。比如,FAL_SERVER = PrimaryDB,此处PrimaryDB是一个TNS name,指向primary库。
FAL_CLIENT指定一个FAL客户端的名字，以便FAL Server可以引用standby库，这也是一个TNS name，primary库必须适当配置此TNS name指向stanby库。这个参数也是在standby库端设置。比如，FAL_CLIENT = StandbyDB,StandbyDB是standby库的TNS name。
FAL_CLIENT和FAL_SERVER应该成对设置或改变。
这两个参数只需在standby库设置，但也可以在primary库设置这两个参数，以方便switchover或failover时primary库转变为standby角色
备注：上面修改的参数有的需要重启数据库才能生效，下面为重启数据库步骤
SYS@LHR11G> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SYS@LHR11G> startup
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
Database mounted.
Database opened.
3.2.6修改监听配置文件
3.2.6.1添加静态注册信息
[oracle@oracleprimary bin]$ vim $ORACLE_HOME/network/admin/listener.ora
-- 追加如下内容：
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME = LHR11G)
(ORACLE_HOME = /u01/app/oracle/product/11.2.0.4/dbhome_1)
(SID_NAME = LHR11G)
)
)
3.2.6.2使新增加的监听生效：
[oracle@oracleprimary admin]$ lsnrctl reload
LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 20-SEP-2022 07:18:42
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
The command completed successfully
------确认新增加的静态监听有效：
[oracle@oracleprimary admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 20-SEP-2022 07:18:52
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.4.0 - Production
Start Date 20-SEP-2022 04:03:03
Uptime 0 days 3 hr. 15 min. 48 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/product/11.2.0.4/dbhome_1/network/admin/listener.ora
Listener Log File /u01/app/oracle/diag/tnslsnr/oracleprimary/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=oracleprimary)(PORT=1521)))
Services Summary...
Service "LHR11G" has 2 instance(s).
Instance "LHR11G", status UNKNOWN, has 1 handler(s) for this service...
Instance "LHR11G", status READY, has 1 handler(s) for this service...
Service "LHR11GXDB" has 1 instance(s).
Instance "LHR11G", status READY, has 1 handler(s) for this service...
The command completed successfully
注意：如果主库上的监听之前已经配置过，这里可以忽略该步骤。
3.2.7修改TNS配置文件
[oracle@oracleprimary admin]$ vim $ORACLE_HOME/network/admin/tnsnames.ora
---编辑内容如下
LHR11G =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.140)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = LHR11G)
)
)
LHR11GS =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.141)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = LHR11GS)
)
)
3.2.7.1配置完后，确保在任意一端上都能tnsping通对方：
[oracle@oracleprimary admin]$ tnsping LHR11G
[oracle@oracleprimary admin]$ tnsping LHR11GS
3.2.8 重启监听服务
[oracle@oracleprimary admin]$ lsnrctl stop
LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 20-SEP-2022 09:54:24
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
The command completed successfully
[oracle@oracleprimary admin]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 20-SEP-2022 09:54:30
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Starting /u01/app/oracle/product/11.2.0.4/dbhome_1/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.2.0.4.0 - Production
System parameter file is /u01/app/oracle/product/11.2.0.4/dbhome_1/network/admin/listener.ora
Log messages written to /u01/app/oracle/diag/tnslsnr/oracleprimary/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=oracleprimary)(PORT=1521)))
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.4.0 - Production
Start Date 20-SEP-2022 09:54:30
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/product/11.2.0.4/dbhome_1/network/admin/listener.ora
Listener Log File /u01/app/oracle/diag/tnslsnr/oracleprimary/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=oracleprimary)(PORT=1521)))
Services Summary...
Service "LHR11G" has 1 instance(s).
Instance "LHR11G", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
3.2.9 备份参数文件，将其拷贝到备库中
-- 创建参数文件，修改后用于备库
SYS@LHR11G> create pfile='/tmp/initLHR11GS.ora' from spfile;
File created.
-- 将pfile拷贝到备库、
-- 先从主库容器拷贝到备库的宿主机中
[oracle@oracleprimary tmp]$ scp /tmp/initLHR11GS.ora [email protected]:/tmp
[email protected]'s password:
initLHR11GS.ora 100% 1581 1.5KB/s 00:00
-- 在从备库的宿主机拷贝到备库容器
[oracle@oraclestandby dbs]$ scp [email protected]:/tmp/initLHR11GS.ora /u01/app/oracle/product/11.2.0.4/dbhome_1/dbs
The authenticity of host '192.168.1.141 (192.168.1.141)' can't be established.
RSA key fingerprint is b2:73:bc:7a:76:33:cc:2d:a5:de:03:c9:e5:db:2b:f9.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.1.141' (RSA) to the list of known hosts.
[email protected]'s password:
initLHR11GS.ora 100% 1581 1.5KB/s 00:00
3.2.10 备份密码文件，将其拷贝到到备库中
[oracle@oracleprimary ~]$ cd $ORACLE_HOME/dbs
-- 知道的密码的，可以直接远程复制 scp orapwLHR11G 192.168.1.141:/u01/app/oracle/product/11.2.0.4/dbhome_1/dbs
-- 先从主库容器拷贝到备库的宿主机中
[oracle@oracleprimary dbs]$ scp orapwLHR11G [email protected]:/tmp/orapwLHR11G_BAK
[email protected]'s password:
orapwLHR11G 100% 1536 1.5KB/s 00:00
-- 再从备库的宿主机拷贝到备库容器
[oracle@oraclestandby dbs]$ scp [email protected]:/tmp/orapwLHR11G_BAK /u01/app/oracle/product/11.2.0.4/dbhome_1/dbs
[email protected]'s password:
orapwLHR11G_BAK 100% 1536 1.5KB/s 00:00
3.2.10 备份控制文件以及数据文件，将其拷贝到到备库中
主要是用于本地恢复，对于网络情况不是很好或者文件比较大的情况是不错的选择
--- 创建控制文件备份目录
[oracle@oracleprimary dbs]$ mkdir -p /home/oracle/LHR11G_BACKUP/controlfile/
[oracle@oracleprimary dbs]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Fri Sep 23 16:48:24 2022
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
--- 创建控制文件到目录
SYS@LHR11G> alter database create standby controlfile as '/home/oracle/LHR11G_BACKUP/controlfile/LHR11GS.ctl';
Database altered.
SYS@LHR11G> exit
--- 创建数据文件备份目录
[oracle@oracleprimary controlfile]$ mkdir -p /home/oracle/LHR11G_BACKUP/datafile
[oracle@oracleprimary controlfile]$ rman target /
Recovery Manager: Release 11.2.0.4.0 - Production on Fri Sep 23 16:51:25 2022
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
connected to target database: LHR11G (DBID=2007947551)
--- 创建数据文件到目录
RMAN> backup database format '/home/oracle/LHR11G_BACKUP/datafile/full_%U.bak' plus archivelog format '/home/oracle/LHR11G_BACKUP/datafile/arch_%U.bak';
--- ..........
这里省略，主要观察有没有错误，没有的话就是数据文件备份成功了-----------
--- 检查备份文件是否都生成了
[oracle@oracleprimary datafile]$ cd /home/oracle/LHR11G_BACKUP/
[oracle@oracleprimary LHR11G_BACKUP]$ ll
total 0
drwxr-xr-x 2 oracle oinstall 46 Sep 23 16:49 controlfile
drwxr-xr-x 2 oracle oinstall 122 Sep 23 16:52 datafile
[oracle@oracleprimary LHR11G_BACKUP]$ cd controlfile/
[oracle@oracleprimary controlfile]$ ll
total 19040
-rw-r----- 1 oracle oinstall 9748480 Sep 23 16:49 LHR11GS.ctl
[oracle@oracleprimary controlfile]$ cd ../datafile/
[oracle@oracleprimary datafile]$ ll
total 1327740
-rw-r----- 1 oracle oinstall 162791936 Sep 23 16:52 arch_0g18evih_1_1.bak
-rw-r----- 1 oracle oinstall 8192 Sep 23 16:52 arch_0j18evis_1_1.bak
-rw-r----- 1 oracle oinstall 1186971648 Sep 23 16:52 full_0h18evii_1_1.bak
-rw-r----- 1 oracle oinstall 9830400 Sep 23 16:52 full_0i18eviq_1_1.bak
-- -- 先从主库容器拷贝到备库的宿主机中
[oracle@oracleprimary ~]$ scp -r /home/oracle/LHR11G_BACKUP [email protected]:/tmp/LHR11G_BACKUP
[email protected]'s password: 100% 9520KB 9.3MB/s 00:00
LHR11GS.ctl 100% 9520KB 9.3MB/s 00:00
arch_0g18evih_1_1.bak 100% 155MB 155.3MB/s 00:01
full_0h18evii_1_1.bak 100% 1132MB 141.5MB/s 00:08
full_0i18eviq_1_1.bak 100% 9600KB 9.4MB/s 00:00
arch_0j18evis_1_1.bak
-- 再从备库的宿主机拷贝到备库容器
[oracle@oraclestandby controlfile]$ scp -r [email protected]:/tmp/LHR11G_BACKUP /home/oracle/LHR11G_BACKUP
3.3备数据库配置
3.3.1 修改参数文件
[oracle@oraclestandby dbs]$ vim $ORACLE_HOME/dbs/initLHR11GS.ora
| 注意红部分 |
|---|
| LHR11GS .__db_cache_size=188743680 |
LHR11GS .__java_pool_size=4194304
LHR11GS .__large_pool_size=8388608
LHR11GS .__oracle_base=’/u01/app/oracle’#ORACLE_BASE set from environment
LHR11GS .__pga_aggregate_target=83886080
LHR11GS .__sga_target=327155712
LHR11GS .__shared_io_pool_size=0
LHR11GS .__shared_pool_size=117440512
LHR11GS.__streams_pool_size=0
*.audit_file_dest=’/u01/app/oracle/admin/LHR11GS/adump’
*.audit_trail=‘db’
*.compatible=‘11.2.0.4.0’
*.control_files=’/data/LHR11GS/controlfile/control01.ctl’,’/data/LHR11GS/controlfile/control02.ctl’
*.db_block_size=8192
*.db_domain=’’
*.db_file_name_convert=’/data/LHR11G/datafile’,’/data/LHR11GS/datafile’
*.db_name=‘LHR11G’
*.db_recovery_file_dest=’/data/LHR11GS/recoverydest’
*.db_recovery_file_dest_size=5368709120
*.diagnostic_dest=’/u01/app/oracle’
*.dispatchers=’(PROTOCOL=TCP) (SERVICE=LHR11GSXDB)’
*.fal_client=‘LHR11GS’
*.fal_server=‘LHR11G’
*.job_queue_processes=1000
*.log_archive_config=‘dg_config=(LHR11GS,LHR11G)’
*.log_archive_dest_1=‘location=/data/LHR11GS/archivelog/ valid_for=(all_logfiles,all_roles) db_unique_name=LHR11GS’
*.log_archive_dest_2=‘service=LHR11G lgwr async valid_for=(online_logfile,primary_role) db_unique_name=LHR11G’
*.log_archive_dest_state_1=‘enable’
*.log_archive_dest_state_2=‘enable’
*.log_file_name_convert=’/data/LHR11G/onlinelog’,’/data/LHR11GS/onlinelog’
*.open_cursors=300
*.pga_aggregate_target=81788928
*.processes=150
*.remote_login_passwordfile=‘EXCLUSIVE’
*.sga_target=327155712
*.standby_file_management=‘AUTO’
*.undo_tablespace=‘UNDOTBS1’
3.3.2 修改密码文件
修改之前从主库拷贝过来的密码文件，具体如下：
[oracle@oraclestandby dbs]$ cd $ORACLE_HOME/dbs
[oracle@oraclestandby dbs]$ mv orapwLHR11G_BAK orapwLHR11GS
3.3.3 创建相应的文件目录
[oracle@oraclestandby dbs]$ mkdir -p /u01/app/oracle/admin/LHR11GS/adump #审计文件目标目录audit_file_dest
[root@oraclestandby /]# mkdir -p /data/LHR11GS/
[root@oraclestandby /]# chown oracle:dba /data/LHR11GS/
[root@oraclestandby /]# su - oracle
[oracle@oraclestandby ~]$ mkdir -p /data/LHR11GS/recoverydest #设置闪回路径
[oracle@oraclestandby ~]$ mkdir -p /data/LHR11GS/archivelog #设置归档路径
[oracle@oraclestandby ~]$ mkdir -p /data/LHR11GS/datafile #主备数据文件转换目录 db_file_name_convert
[oracle@oraclestandby ~]$ mkdir -p /data/LHR11GS/onlinelog #主备日志文件转换目录 log_file_name_convert
[oracle@oraclestandby ~]$ mkdir -p /data/LHR11GS/controlfile
3.3.4 修改监听配置文件
[oracle@oraclestandby ~]$ vim $ORACLE_HOME/network/admin/listener.ora
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = oraclestandby)(PORT = 1521))
)
)
ADR_BASE_LISTENER = /u01/app/oracle
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME = LHR11GS)
(ORACLE_HOME = /u01/app/oracle/product/11.2.0.4/dbhome_1)
(SID_NAME = LHR11GS)
)
)
3.3.5 修改TNS配置文件
[oracle@oraclestandby ~]$ vim $ORACLE_HOME/network/admin/tnsnames.ora
LHR11G =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST =192.168.1.140)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = LHR11G)
)
)
LHR11GS =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST =192.168.1.141)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = LHR11GS)
)
)
3.3.6 重启监听服务
[oracle@oraclestandby 11.2.0.4]$ lsnrctl stop
LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 20-SEP-2022 11:57:51
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
The command completed successfully
[oracle@oraclestandby 11.2.0.4]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 20-SEP-2022 11:58:08
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Starting /u01/app/oracle/product/11.2.0.4/dbhome_1/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.2.0.4.0 - Production
System parameter file is /u01/app/oracle/product/11.2.0.4/dbhome_1/network/admin/listener.ora
Log messages written to /u01/app/oracle/diag/tnslsnr/oraclestandby/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=oraclestandby)(PORT=1521)))
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.4.0 - Production
Start Date 20-SEP-2022 11:58:08
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/product/11.2.0.4/dbhome_1/network/admin/listener.ora
Listener Log File /u01/app/oracle/diag/tnslsnr/oraclestandby/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=oraclestandby)(PORT=1521)))
Services Summary...
Service "LHR11GS" has 1 instance(s).
Instance "LHR11GS", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
3.3.7 启动数据库到nomount状态
[oracle@oraclestandby onlinelog]$ export ORACLE_SID=LHR11GS
[oracle@oraclestandby onlinelog]$ sas
SQL*Plus: Release 11.2.0.4.0 Production on Wed Sep 21 05:16:29 2022
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to an idle instance.
SYS@LHR11GS> startup nomount pfile='/u01/app/oracle/product/11.2.0.4/dbhome_1/dbs/initLHR11GS.ora';
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
SYS@LHR11GS> create spfile from pfile;
File created.
3.3.8 验证监听和TNS配置
3.3.8.1 主库上验证:
[oracle@oracleprimary ~]$ sqlplus sys/sys@LHR11G as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Wed Sep 21 06:48:48 2022
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SYS@LHR11G> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@oracleprimary ~]$ sqlplus sys/sys@LHR11GS as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Wed Sep 21 06:48:54 2022
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SYS@LHR11GS> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
3.3.8.2 备库上验证：
[oracle@oraclestandby dbs]$ sqlplus sys/sys@LHR11GS as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Wed Sep 21 06:50:12 2022
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SYS@LHR11GS> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@oraclestandby dbs]$ sqlplus sys/sys@LHR11G as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Wed Sep 21 06:50:18 2022
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SYS@LHR11G> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
3.3.9 恢复数据库
这里采用在线恢复
[oracle@oracleprimary ~]$ rman target sys/sys@LHR11G auxiliary sys/sys@LHR11GS
Recovery Manager: Release 11.2.0.4.0 - Production on Sat Sep 24 13:50:24 2022
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
connected to target database: LHR11G (DBID=2007947551)
connected to auxiliary database: LHR11G (not mounted)
RMAN> duplicate target database for standby from active database nofilenamecheck;
-----。。。。。---------
Finished Duplicate Db at 2022-09-24 13:51:11
RMAN> exit
3.3.10 开启实时同步
完成了上述的步骤，备库还没有打开
SYS@LHR11GS> shutdown immediate;
ORA-01109: database not open
Database dismounted.
ORACLE instance shut down.
SYS@LHR11GS> startup
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
Database mounted.
Database opened.
--- 开启实时同步
SYS@LHR11GS> alter database recover managed standby database using current logfile disconnect from session;
Database altered.
3.3.11 开启flashback
上面DataGuard搭建好之后，千万不要忘了把备库的flashback打开，具体如下：
---- 取消实时同步
SYS@LHR11GS> alter database recover managed standby database cancel;
Database altered.
-- 关闭数据库
SYS@LHR11GS> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
-- 打开到mount状态
SYS@LHR11GS> startup mount
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
Database mounted.
--- 开启flashback
SYS@LHR11GS> alter database flashback on;
Database altered.
-- open数据库
SYS@LHR11GS> alter database open;
Database altered.
-- 开启实时同步
SYS@LHR11GS> alter database recover managed standby database using current logfile disconnect from session;
Database altered.
3.4验证DG同步
上面已经把DataGurad搭建完，下面介绍如何验证DataGuard是否能实时同步
3.4.1 通过查看archive_log_dest_2列是否有error报错，如果有报错，则需要先根据报错内容解决问题
[oracle@oracleprimary ~]$ sas
SQL*Plus: Release 11.2.0.4.0 Production on Sat Sep 24 14:17:24 2022
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SYS@LHR11G> col dest_name format a30
SYS@LHR11G> col error format a20
SYS@LHR11G> select dest_name,error from v$archive_dest;
DEST_NAME ERROR
------------------------------ --------------------
LOG_ARCHIVE_DEST_1
LOG_ARCHIVE_DEST_2
LOG_ARCHIVE_DEST_3
LOG_ARCHIVE_DEST_4
LOG_ARCHIVE_DEST_5
LOG_ARCHIVE_DEST_6
LOG_ARCHIVE_DEST_7
LOG_ARCHIVE_DEST_8
LOG_ARCHIVE_DEST_9
LOG_ARCHIVE_DEST_10
LOG_ARCHIVE_DEST_11
LOG_ARCHIVE_DEST_12
LOG_ARCHIVE_DEST_13
LOG_ARCHIVE_DEST_14
LOG_ARCHIVE_DEST_15
LOG_ARCHIVE_DEST_16
LOG_ARCHIVE_DEST_17
LOG_ARCHIVE_DEST_18
LOG_ARCHIVE_DEST_19
LOG_ARCHIVE_DEST_20
LOG_ARCHIVE_DEST_21
LOG_ARCHIVE_DEST_22
LOG_ARCHIVE_DEST_23
LOG_ARCHIVE_DEST_24
LOG_ARCHIVE_DEST_25
LOG_ARCHIVE_DEST_26
LOG_ARCHIVE_DEST_27
LOG_ARCHIVE_DEST_28
LOG_ARCHIVE_DEST_29
LOG_ARCHIVE_DEST_30
LOG_ARCHIVE_DEST_31
31 rows selected.
注意：上面显示没有报错
3.4.2 查询主库最大归档序号，一致即归档同步成功。
--------主库上执行：
SYS@LHR11G> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
65
--------备库上执行：
SYS@LHR11GS> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
65
---- 主库上尝试执行日志切换，查看归档序号的变化
SYS@LHR11G> alter system archive log current;
--- 主库上执行，查看最大归档序号
System altered.
SYS@LHR11G> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
66
---备库上再次验证：
SYS@LHR11GS> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
66
3.4.3. 查看主备库状态
----- 主库上执行：
SYS@LHR11G> select switchover_status,database_role from v$database;
SWITCHOVER_STATUS DATABASE_ROLE
---------------------------------------- --------------------------------
SESSIONS ACTIVE PRIMARY
----- 备库上执行：
SYS@LHR11GS> select switchover_status,database_role from v$database;
SWITCHOVER_STATUS DATABASE_ROLE
---------------------------------------- --------------------------------
NOT ALLOWED PHYSICAL STANDBY
3.4.4 可以创建一个table进行测试
--- 主库上执行：
SYS@LHR11G> create table dg(id number);
Table created.
SYS@LHR11G> insert into dg values(1);
1 row created.
SYS@LHR11G> commit;
Commit complete.
SYS@LHR11G> select * from dg;
ID
----------
1
---- 备库上执行
SYS@LHR11GS> select * from dg;
ID
----------
1
上面说明DG是同步的。
3.5DG切换与恢复
我们配置DG的目的就是为了在主库出现故障时，备库能够提供服务，保证业务的正常运行。DG的故障切换分为switchover和failover两种:
3.5.1 switchover
switchover是用户有计划的进行停机切换，能够保证不丢失数据，下面我们来看下switchover是怎样操作的：
步骤1：主库上操作：
SYS@LHR11G> select switchover_status,database_role from v$database;
SWITCHOVER_STATUS DATABASE_ROLE
---------------------------------------- --------------------------------
SESSIONS ACTIVE PRIMARY
#######################-注意：上面查询结果为TO STANDBY 或 SESSIONS ACTIVE表明可以进行切换备库
---- 切换数据库模式为 PHYSICAL STANDBY
SYS@LHR11G> alter database commit to switchover to physical standby;
Database altered.
SYS@LHR11G> startup mount
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
Database mounted.
SYS@LHR11G> select database_role from v$database;
DATABASE_ROLE
--------------------------------
PHYSICAL STANDBY
步骤2：备库上操作：
SYS@LHR11GS> select switchover_status,database_role from v$database;
SWITCHOVER_STATUS DATABASE_ROLE
---------------------------------------- --------------------------------
TO PRIMARY PHYSICAL STANDBY
###### 注意：上面查询结果显示为TO PRIMARY 或 SESSIONS ACTIVE表明可以切换成主库；
---- 现在可以把备库切换成主库：
SYS@LHR11GS> alter database commit to switchover to primary with session shutdown;
Database altered.
SYS@LHR11GS> alter database open;
Database altered.
SYS@LHR11GS> select switchover_status,database_role,open_mode from v$database;
SWITCHOVER_STATUS DATABASE_ROLE OPEN_MODE
---------------------------------------- -------------------------------- ----------------------------------------
RESOLVABLE GAP PRIMARY READ WRITE
步骤3：原主库，现备库上执行
记住：这时候需要在现在的备库（原先的主库）开启实时同步
SYS@LHR11G> alter database open;
Database altered.
--- 开启实时同步
SYS@LHR11G> alter database recover managed standby database using current logfile disconnect from session;
Database altered.
SYS@LHR11G> select switchover_status,database_role from v$database;
SWITCHOVER_STATUS DATABASE_ROLE
---------------------------------------- --------------------------------
NOT ALLOWED PHYSICAL STANDBY
原备库，现主库上执行
SYS@LHR11GS> select switchover_status,database_role,open_mode from v$database;
SWITCHOVER_STATUS DATABASE_ROLE OPEN_MODE
---------------------------------------- -------------------------------- ----------------------------------------
TO STANDBY PRIMARY READ WRITE
3.5.2 failover
failover是当主库真正出现严重系统故障，如数据库宕机，软硬件故障导致主库不能支持服务，从而进行的切换动作。
注意：为了能够在failover后能够恢复DG,需要在主库上开启flashback，如果不开启flashback的话，DG就可能需要重新搭建
以上步骤主备库已经切换了
步骤1：模拟主库宕机
[root@davystandby ~]# docker stop dbstandby
dbst
步骤2：备库操作
由于主库已经不可访问，下面所有的操作都在备库完成：
----停止实时同步
SYS@LHR11G> alter database recover managed standby database cancel;
Database altered.
SYS@LHR11G> select switchover_status,database_role,open_mode from v$database;
SWITCHOVER_STATUS DATABASE_ROLE OPEN_MODE
---------------------------------------- -------------------------------- ----------------------------------------
NOT ALLOWED PHYSICAL STANDBY READ ONLY
SYS@LHR11G> alter database recover managed standby database finish force;
Database altered.
SYS@LHR11G> select switchover_status,database_role,open_mode from v$database;
SWITCHOVER_STATUS DATABASE_ROLE OPEN_MODE
---------------------------------------- -------------------------------- ----------------------------------------
TO PRIMARY PHYSICAL STANDBY READ ONLY
SYS@LHR11G> alter database commit to switchover to primary;
Database altered.
SYS@LHR11G> alter database open;
Database altered.
SYS@LHR11G> select switchover_status,database_role,open_mode from v$database;
SWITCHOVER_STATUS DATABASE_ROLE OPEN_MODE
---------------------------------------- -------------------------------- ----------------------------------------
RESOLVABLE GAP PRIMARY READ WRITE
至此failover操作完成，原来的备库已经切换为主库，可以给业务提供服务了。
3.5.2 failover恢复
上面提到了failover，这种情形是当主库真正出现异常之后，才会执行的操作，那么我们执行过failover 之后，如何在重新构建DG，这里我们利用flashback database来重构，具体方法如下：
步骤1：在新的主库上执行：
SYS@LHR11G> select switchover_status,database_role,open_mode from v$database;
SWITCHOVER_STATUS DATABASE_ROLE OPEN_MODE
---------------------------------------- -------------------------------- ----------------------------------------
RESOLVABLE GAP PRIMARY READ WRITE
SYS@LHR11G> select to_char(standby_became_primary_scn) from v$database;
TO_CHAR(STANDBY_BECAME_PRIMARY_SCN)
--------------------------------------------------------------------------------
1383514
步骤2：模拟启动原主库，现在主库启动
[root@davystandby ~]# docker start dbstandby
dbstandby
[root@davystandby tmp]# docker exec -it dbstandby bash
步骤3：备库操作
[oracle@oraclestandby ~]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 24-SEP-2022 15:42:11
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Starting /u01/app/oracle/product/11.2.0.4/dbhome_1/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.2.0.4.0 - Production
System parameter file is /u01/app/oracle/product/11.2.0.4/dbhome_1/network/admin/listener.ora
Log messages written to /u01/app/oracle/diag/tnslsnr/oraclestandby/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=oraclestandby)(PORT=1521)))
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
STATUS of the LISTENER
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.4.0 - Production
Start Date 24-SEP-2022 15:42:13
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/product/11.2.0.4/dbhome_1/network/admin/listener.ora
Listener Log File /u01/app/oracle/diag/tnslsnr/oraclestandby/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=oraclestandby)(PORT=1521)))
Services Summary...
Service "LHR11G" has 1 instance(s).
Instance "LHR11G", status UNKNOWN, has 1 handler(s) for this service...
Service "LHR11GS" has 1 instance(s).
Instance "LHR11GS", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
[oracle@oraclestandby ~]$ sas
SQL*Plus: Release 11.2.0.4.0 Production on Sat Sep 24 15:42:28 2022
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
------启动数据库为mount状态
SYS@LHR11GS> startup mount
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
Database mounted.
---执行闪回，这个值为在新主库上查询到的SCN值
SYS@LHR11GS> flashback database to scn 1383514;
Flashback complete.
SYS@LHR11GS> alter database convert to physical standby;
Database altered.
SYS@LHR11GS> shutdown immediate
ORA-01507: database not mounted
ORACLE instance shut down.
SYS@LHR11GS> startup
ORACLE instance started.
Total System Global Area 325685248 bytes
Fixed Size 2252944 bytes
Variable Size 171970416 bytes
Database Buffers 146800640 bytes
Redo Buffers 4661248 bytes
Database mounted.
Database opened.
--开启实时同步
SYS@LHR11GS> alter database recover managed standby database using current logfile disconnect from session;
Database altered.
SYS@LHR11GS> select switchover_status,database_role,open_mode from v$database;
SWITCHOVER_STATUS DATABASE_ROLE OPEN_MODE
---------------------------------------- -------------------------------- ----------------------------------------
SWITCHOVER PENDING PHYSICAL STANDBY READ ONLY WITH APPLY
到此failover 恢复已经完成，关于如何验证DG方法如上，这里不在介绍。