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一、环境准备
1、环境规划
备注：C机器只需要安装好数据库即可，不用建实例，这里我们为了方便直接一键安装3台机器。
安装脚本如下：
https://mp.weixin.qq.com/s/zzPEkBmJB-Rx6nve9iA7dQ
B机器，我们需要修改dm,ini配置的实例为BACK
2、集群架构
搭建的主备集群架构如下图：
二、部署主备基本配置
(一)配置A机器
1、开启归档日志
[dmdba@~]$disql SYSDBA/Ceshi@5235
SQL> ALTER DATABASE MOUNT;
SQL> ALTER DATABASE ARCHIVELOG;
SQL> ALTER DATABASE ADD ARCHIVELOG 'DEST=/dm/arch, TYPE=LOCAL, FILE_SIZE=1024,
SPACE_LIMIT=51200';
SQL> ALTER DATABASE OPEN;
2、备份数据
SQL> BACKUP DATABASE BACKUPSET '/dm/data/PROD/bak/BACKUP_FILE';
3、修改 dm.ini
SQL> SP_SET_PARA_VALUE (2,'PORT_NUM',5236);
SQL> SP_SET_PARA_VALUE (2,'DW_INACTIVE_INTERVAL',60);
SQL> SP_SET_PARA_VALUE (2,'ALTER_MODE_STATUS',0);
SQL> SP_SET_PARA_VALUE (2,'ENABLE_OFFLINE_TS',2);
SQL> SP_SET_PARA_VALUE (2,'MAL_INI',1);
SQL> SP_SET_PARA_VALUE (2,'RLOG_SEND_APPLY_MON',64);
4、关闭前台实例服务
[dmdba@localhost ~]$ DmServicePROD stop
5、修改 dmarch.ini
[dmdba@localhost ~]$ vi dm/data/PROD/dmarch.ini
将内容完全修改为以下内容：
#DaMeng Database Archive Configuration file
#this is comments
ARCH_WAIT_APPLY = 0
[ARCHIVE_LOCAL1]
ARCH_TYPE = LOCAL
ARCH_DEST = dm/arch
ARCH_FILE_SIZE = 1024
ARCH_SPACE_LIMIT = 51200
ARCH_FLUSH_BUF_SIZE = 2
ARCH_HANG_FLAG = 1
[ARCHIVE_REALTIME1]
ARCH_TYPE = REALTIME #实时归档类型
ARCH_DEST = PROD #实时归档目标实例名
6、创建 dmmal.ini
[dmdba@localhost ~]$ mkdir malpath
[dmdba@localhost ~]$ vi dm/data/PROD/dmmal.ini
添加以下内容：
MAL_CHECK_INTERVAL = 10 #MAL 链路检测时间间隔
MAL_CONN_FAIL_INTERVAL = 10 #判定 MAL 链路断开的时间
MAL_TEMP_PATH = dm/malpath/ #临时文件目录
MAL_BUF_SIZE = 512 #单个 MAL 缓存大小，单位 MB
MAL_SYS_BUF_SIZE = 2048 #MAL 总大小限制，单位 MB
MAL_COMPRESS_LEVEL = 0 #MAL 消息压缩等级，0 表示不压缩
[MAL_INST1]
MAL_INST_NAME = PROD #实例名，和 dm.ini 的 INSTANCE_NAME 一致
MAL_HOST = 192.168.1.1 #MAL 系统监听 TCP 连接的 IP 地址
MAL_PORT = 5336 #MAL 系统监听 TCP 连接的端口
MAL_INST_HOST = 192.168.220.135 #实例的对外服务 IP 地址
MAL_INST_PORT = 5236 #实例对外服务端口，和 dm.ini 的 PORT_NUM 一致
MAL_DW_PORT = 5436 #实例对应的守护进程监听 TCP 连接的端口
MAL_INST_DW_PORT = 5536 #实例监听守护进程 TCP 连接的端口
[MAL_INST2]
MAL_INST_NAME = BACK
MAL_HOST = 192.168.1.2
MAL_PORT = 5336
MAL_INST_HOST = 192.168.220.136
MAL_INST_PORT = 5236
MAL_DW_PORT = 5436
MAL_INST_DW_PORT = 5536
7、创建 dmwatcher.ini
[dmdba@localhost ~]$ vi dm/data/PROD/dmwatcher.ini
添加以下内容：
[GRP1]
DW_TYPE = GLOBAL #全局守护类型
DW_MODE = AUTO #MANUAL：故障手切 AUTO：故障自切
DW_ERROR_TIME = 20 #远程守护进程故障认定时间
INST_ERROR_TIME = 20 #本地实例故障认定时间
INST_RECOVER_TIME = 60 #主库守护进程启动恢复的间隔时间
INST_OGUID = 45331 #守护系统唯一 OGUID 值
INST_INI = dm/data/PROD/dm.ini #dm.ini 文件路径
INST_AUTO_RESTART = 1 #打开实例的自动启动功能
INST_STARTUP_CMD = dm/dbms/bin/dmserver #命令行方式启动
RLOG_SEND_THRESHOLD = 0 #指定主库发送日志到备库的时间阈值，默认关闭
RLOG_APPLY_THRESHOLD = 0 #指定备库重演日志的时间阈值，默认关闭
8、拷贝备份文件到B机器
[dmdba@localhost ~]$ scp -r dm/data/PROD/bak/BACKUP_FILE dmdba@192.168.220.136:/dm/data/
9、注册服务
[root@localhost ~]# dm/dbms/script/root/dm_service_uninstaller.sh -n DmServicePROD #我这里一键安装脚本已经注册了，所以需要执行此步骤
Whether to delete the service(DmServicePROD) (Y/y:yes N/n:no): Y
Removed etc/systemd/system/multi-user.target.wants/DmServicePROD.service.
Finished to delete the service file(/usr/lib/systemd/system/DmServicePROD.service)
Finished to delete the service(DmServicePROD)
[root@localhost ~]# dm/dbms/script/root/dm_service_installer.sh -t dmserver -p PROD -dm_ini dm/data/PROD/dm.ini -m mount
Created symlink etc/systemd/system/multi-user.target.wants/DmServicePROD.service → usr/lib/systemd/system/DmServicePROD.service.
Finished to create the service (DmServicePROD)
[root@localhost ~]# dm/dbms/script/root/dm_service_installer.sh -t dmwatcher -p Watcher -watcher_ini dm/data/PROD/dmwatcher.ini
Created symlink etc/systemd/system/multi-user.target.wants/DmWatcherServiceWatcher.service → usr/lib/systemd/system/DmWatcherServiceWatcher.service.
Finished to create the service (DmWatcherServiceWatcher)
（二）配置 B 机器
1、恢复数据
[dmdba@localhost ~]$ dm/dbms/bin/dmrman CTLSTMT="RESTORE DATABASE '/dm/data/PROD/dm.ini' FROM BACKUPSET '/dm/data/BACKUP_FILE'"
dmrman V8
RESTORE DATABASE '/dm/data/PROD/dm.ini' FROM BACKUPSET '/dm/data/BACKUP_FILE'
file dm.key not found, use default license!
[Percent:100.00%][Speed:0.00M/s][Cost:00:00:03][Remaining:00:00:00]
restore successfully.
time used: 00:00:03.480
[dmdba@localhost ~]$ dm/dbms/bin/dmrman CTLSTMT="RECOVER DATABASE '/dm/data/PROD/dm.ini' FROM BACKUPSET '/dm/data/BACKUP_FILE'"
dmrman V8
RECOVER DATABASE '/dm/data/PROD/dm.ini' FROM BACKUPSET '/dm/data/BACKUP_FILE'
file dm.key not found, use default license!
[Percent:100.00%][Speed:0.00PKG/s][Cost:00:00:00][Remaining:00:00:00]
recover successfully!
time used: 00:00:03.536
[dmdba@localhost ~]$ dm/dbms/bin/dmrman CTLSTMT="RECOVER DATABASE '/dm/data/PROD/dm.ini' UPDATE DB_MAGIC"
dmrman V8
RECOVER DATABASE '/dm/data/PROD/dm.ini' UPDATE DB_MAGIC
file dm.key not found, use default license!
recover successfully!
time used: 00:00:01.250
2、配置dmarch.ini
[dmdba@localhost PROD]$ vi dm/data/PROD/dmarch.ini
#DaMeng Database Archive Configuration file
#this is comments
ARCH_WAIT_APPLY = 1
[ARCHIVE_LOCAL1]
ARCH_TYPE = LOCAL
ARCH_DEST = dm/arch
ARCH_FILE_SIZE = 128
ARCH_SPACE_LIMIT = 0
ARCH_FLUSH_BUF_SIZE = 0
ARCH_HANG_FLAG = 1
[ARCHIVE_TIMELY1]
ARCH_TYPE = REALTIME #即时归档类型
ARCH_DEST = PROD #即时归档目标实例名
3、创建 dmmal.ini
[dmdba@localhost dm]$ mkdir malpath
[dmdba@localhost dm]$ vi dm/data/PROD/dmmal.ini
MAL_CHECK_INTERVAL = 10 #MAL 链路检测时间间隔
MAL_CONN_FAIL_INTERVAL = 10 #判定 MAL 链路断开的时间
MAL_TEMP_PATH = dm/malpath/ #临时文件目录
MAL_BUF_SIZE = 512 #单个 MAL 缓存大小，单位 MB
MAL_SYS_BUF_SIZE = 2048 #MAL 总大小限制，单位 MB
MAL_COMPRESS_LEVEL = 0 #MAL 消息压缩等级，0 表示不压缩
[MAL_INST1]
MAL_INST_NAME = PROD #实例名，和 dm.ini 的 INSTANCE_NAME 一致
MAL_HOST = 192.168.1.1 #MAL 系统监听 TCP 连接的 IP 地址
MAL_PORT = 5336 #MAL 系统监听 TCP 连接的端口
MAL_INST_HOST = 192.168.220.135 #实例的对外服务 IP 地址
MAL_INST_PORT = 5236 #实例对外服务端口，和 dm.ini 的 PORT_NUM 一致
MAL_DW_PORT = 5436 #实例对应的守护进程监听 TCP 连接的端口
MAL_INST_DW_PORT = 5536 #实例监听守护进程 TCP 连接的端口
[MAL_INST2]
MAL_INST_NAME = BACK
MAL_HOST = 192.168.1.2
MAL_PORT = 5336
MAL_INST_HOST = 192.168.220.136
MAL_INST_PORT = 5236
MAL_DW_PORT = 5436
MAL_INST_DW_PORT = 5536
4、创建 dmwatcher.ini
[dmdba@localhost dm]$ vi dm/data/PROD/dmwatcher.ini
添加以下内容：
[GRP1]
DW_TYPE = GLOBAL #全局守护类型
DW_MODE = AUTO #MANUAL：故障手切 AUTO：故障自切
DW_ERROR_TIME = 20 #远程守护进程故障认定时间
INST_ERROR_TIME = 20 #本地实例故障认定时间
INST_RECOVER_TIME = 60 #主库守护进程启动恢复的间隔时间
INST_OGUID = 45331 #守护系统唯一 OGUID 值
INST_INI = dm/data/PROD/dm.ini #dm.ini 文件路径
INST_AUTO_RESTART = 1 #打开实例的自动启动功能
INST_STARTUP_CMD = dm/dbms/bin/dmserver #命令行方式启动
RLOG_SEND_THRESHOLD = 0 #指定主库发送日志到备库的时间阈值，默认关闭
RLOG_APPLY_THRESHOLD = 0 #指定备库重演日志的时间阈值，默认关闭
5、修改dm.ini
[dmdba@localhost dm]$ vi dm/data/PROD/dm.ini
将将MAL_INI = 0 改为MAL_INI = 1
6、注册服务
[root@localhost ~]# dm/dbms/script/root/dm_service_uninstaller.sh -n DmServicePROD
Whether to delete the service(DmServicePROD) (Y/y:yes N/n:no): Y
Removed etc/systemd/system/multi-user.target.wants/DmServicePROD.service.
Finished to delete the service file(/usr/lib/systemd/system/DmServicePROD.service)
Finished to delete the service(DmServicePROD)
[root@localhost ~]# dm/dbms/script/root/dm_service_installer.sh -t dmserver -p BACK -dm_ini dm/data/PROD/dm.ini -m mount
Created symlink etc/systemd/system/multi-user.target.wants/DmServicePROD.service → usr/lib/systemd/system/DmServicePROD.service.
Finished to create the service (DmServicePROD)
[root@localhost ~]# dm/dbms/script/root/dm_service_installer.sh -t dmwatcher -p Watcher -watcher_ini dm/data/PROD/dmwatcher.ini
Created symlink etc/systemd/system/multi-user.target.wants/DmWatcherServiceWatcher.service → usr/lib/systemd/system/DmWatcherServiceWatcher.service.
Finished to create the service (DmWatcherServiceWatcher)
（三）配置C机器
1、配置dmmonitor.ini
[dmdba@localhost ~]$ vi dm/data/PROD/dmmonitor.ini
添加以下内容：
MON_DW_CONFIRM = 1 #0：非确认（故障手切） 1：确认（故障自切）
MON_LOG_PATH = dm/data/PROD/log #监视器日志文件存放路径
MON_LOG_INTERVAL = 60 #每隔 60s 定时记录系统信息到日志文件
MON_LOG_FILE_SIZE = 512 #单个日志大小，单位 MB
MON_LOG_SPACE_LIMIT = 2048 #日志上限，单位 MB
[GRP1]
MON_INST_OGUID = 45331 #组 GRP1 的唯一 OGUID 值
MON_DW_IP = 192.168.220.135:5436
MON_DW_IP = 192.168.220.136:5436
2、注册服务
[root@localhost ~]# dm/dbms/script/root/dm_service_installer.sh -t dmmonitor -p Monitor -monitor_ini dm/data/PROD/dmmonitor.ini
Created symlink etc/systemd/system/multi-user.target.wants/DmMonitorServiceMonitor.service → usr/lib/systemd/system/DmMonitorServiceMonitor.service.
Finished to create the service (DmMonitorServiceMonitor)
[root@localhost ~]#
三、启动读写分离集群（自动切换）
1、启动数据库并设置主备
机器A
[dmdba@localhost ~]$ DmServicePROD start
[dmdba@localhost ~]$ disql
disql V8
username:SYSDBA
password:
Server[LOCALHOST:5236]:mode is normal, state is mount
login used time : 9.257(ms)
SQL> SP_SET_OGUID(45331);
DMSQL executed successfully
used time: 10.589(ms). Execute id is 1.
SQL> ALTER DATABASE PRIMARY;
executed successfully
used time: 28.009(ms). Execute id is 0.
SQL>
机器B
[dmdba@localhost ~]$ DmServiceBACK start
[dmdba@localhost ~]$ disql
disql V8
username:SYSDBA
password:
Server[LOCALHOST:5236]:mode is normal, state is mount
login used time : 51.917(ms)
SQL> SP_SET_OGUID(45331);
DMSQL executed successfully
used time: 9.761(ms). Execute id is 1.
SQL> ALTER DATABASE STANDBY;
executed successfully
used time: 23.159(ms). Execute id is 0.
2、关闭机器A和机器B的数据库
[dmdba@localhost ~]$ DmServicePROD stop 机器A
[dmdba@localhost ~]$ DmServiceBACK stop 机器B
3、启动守护进程
机器B
[dmdba@localhost ~]$ DmWatcherServiceWatcher start
机器A
[dmdba@localhost ~]$ DmWatcherServiceWatcher start
4、启动监控器进程
选择其中一种即可
方法1：
临时启动
[dmdba@localhost PROD]$ mkdir log
[dmdba@localhost PROD]$ dmmonitor /dm/data/PROD/dmmonitor.ini
方法2：
后台启动
[dmdba@localhost PROD]$DmMonitorService start #后台启动
如果想要配置监控器自启动，则必须再建一个普通监视器
[dmdba@localhost PROD]$ cp /dm/data/PROD/dmmonitor.ini /dm/data/PROD/dmmonitor_manual.ini
[dmdba@localhost PROD]$ dmmonitor /dm/data/PROD/dmmonitor_manual.ini
至此DM读写分离自动切换集群已搭建完毕。
查看主备库的状态
SQL> SELECT
CASE
WHEN "STATUS$" = '1' THEN 'Startup'
WHEN "STATUS$" = '2' THEN 'After Redo'
WHEN "STATUS$" = '3' THEN 'MOUNT'
WHEN "STATUS$" = '4' THEN 'OPEN'
WHEN "STATUS$" = '5' THEN 'SUSPEND'
ELSE 'Unknown(' || "STATUS$" || ')'
END "库状态",
CASE
WHEN "ROLE$" = '0' THEN 'Normal'
WHEN "ROLE$" = '1' THEN 'Primary'
WHEN "ROLE$" = '2' THEN 'Standby'
ELSE 'Unknown(' || "ROLE$" || ')'
END "模式"
FROM v$database;
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