启动观察程序并启用快速启动故障转移

将观察程序安装在单独的可用性区域中的 Azure 计算 VM 上，并启用快速启动故障转移。

Observer 是 DGMGRL CLI 中内置的低占用空间客户机，与其他任何客户机一样，它可以在与数据库服务器不同的硬件平台上运行。

Data Guard 中介可以自动化和集中创建、维护和监视 Data Guard 配置。它允许您通过中介的客户机界面在本地或远程执行所有管理操作：

Oracle Enterprise Manager Cloud Control 或
Data Guard 命令行界面，DGMGRL

DGMGRL 命令行是 Oracle AI Database 软件安装的一部分，可从 $ORACLE_HOME/bin/dgmgrl 获取。按照以下步骤启用快速启动故障转移：

在观察程序 VM 上下载和安装 Oracle AI Database 客户机。对于 Linux x64：
```
unzip LINUX.X64_2326100_client.zip
cd client
./runInstaller
```

使用主数据库和备用数据库的连接字符串创建 tnsnames.ora 文件。将建议的连接字符串与 SCAN 名称结合使用：

在观察程序 VM 上编辑 $ORACLE_HOME/network/admin/tnsnames.ora。

vi $ORACLE_HOME/network/admin/tnsnamse.ora

DBZONE1=(DESCRIPTION=(CONNECT_TIMEOUT= 90)(RETRY_COUNT=100)(RETRY_DELAY=3)(TRANSPORT_CONNECT_TIMEOUT=1000ms)(LOAD_BALANCE=off)(ADDRESS_LIST=(LOAD_BALANCE=on)(ADDRESS=(PROTOCOL=TCP)(HOST=scan-vmcluster-1)(PORT=1521)))(CONNECT_DATA=(SERVICE_NAME = DBzone1.ocidelegatedsu.ocivnet1.oraclevcn.com)))

DBZONE2=(DESCRIPTION=(CONNECT_TIMEOUT= 90)(RETRY_COUNT=100)(RETRY_DELAY=3)(TRANSPORT_CONNECT_TIMEOUT=1000ms)(LOAD_BALANCE=off)(ADDRESS_LIST=(LOAD_BALANCE=on)(ADDRESS=(PROTOCOL=TCP)(HOST=scan-mvcluster-2)(PORT=1521)))(CONNECT_DATA=(SERVICE_NAME = DBzone2.ocidelegatedsu.ocivnet2.oraclevcn.com)))

haservice = (DESCRIPTION =
(CONNECT_TIMEOUT= 90)(RETRY_COUNT=100)(RETRY_DELAY=3)(TRANSPORT_CONNECT_TIMEOUT=1000ms)(LOAD_BALANCE=off)
    (ADDRESS_LIST =
        (LOAD_BALANCE=on)
        (ADDRESS = (PROTOCOL = TCP)(HOST=scan-vmcluster-1)(PORT=1521)))
    (ADDRESS_LIST =
        (LOAD_BALANCE=on)
        (ADDRESS = (PROTOCOL = TCP)(HOST=scan-vmcluster-2)(PORT=1521)))      
    (CONNECT_DATA=(SERVICE_NAME = haservice.oracle.com)))

验证与主数据库和备用数据库的连接。

export TNS_ADMIN=$ORACLE_HOME/network/admin

dgmgrl SYS@DBZONE1
...
Connected to "DBzone1"
Connected as SYSDBA.
            
dgmgrl SYS@DBZONE2
...
Connected to "DBzone2"
Connected as SYSDBA.

检查 Data Guard 配置和快速启动故障转移目标设置。

DGMGRL> show configuration
Configuration - db26_dgconf
  Protection Mode: MaxAvailability
  Members:
  DBzone1 - Primary database
    DBzone2 - Physical standby database
Fast-Start Failover:  Disabled
Configuration Status:
SUCCESS   (status updated 20 seconds ago)

DGMGRL> show database DBzone1 FastStartFailoverTarget;
  FastStartFailoverTarget = 'DBzone2'

DGMGRL> show database DBzone2 FastStartFailoverTarget;
  FastStartFailoverTarget = 'DBzone1'

在观察程序 VM 上启动观察程序进程。要在后台运行观察程序，请执行以下操作：

export WALLET_DIR=/u01/app/oracle/product/23.26.0/dbhome_1/network/admin/wallet
mkstore -wrl $WALLET_DIR -create
mkstore -wrl $WALLET_DIR -createCredential 'DBZONE1' sysdg <password>;
mkstore -wrl $WALLET_DIR -createCredential 'DBZONE2' sysdg <password>;
mkstore -wrl $WALLET_DIR -createCredential 'HASERVICE' sysdg <password>;

vi /u01/app/oracle/product/23.26.0/dbhome_1/network/admin/sqlnet.ora
WALLET_LOCATION = (SOURCE = (METHOD = FILE) (METHOD_DATA = (DIRECTORY = /u01/app/oracle/product/23.26.0/dbhome_1/network/admin/wallet)))
SQLNET.WALLET_OVERRIDE = TRUE

dgmgrl SYS@DBZONE1
DGMGRL> START OBSERVER observer3 IN BACKGROUND FILE IS /home/oracle/observer3.dat LOGFILE IS /home/oracle/observer3.log CONNECT IDENTIFIER IS haservice;
Submitted command "START OBSERVER" using connect identifier "haservice"

DGMGRL> show observer
Configuration - db26_dgconf
  Fast-Start Failover:     DISABLED
Observer "observer3"(23.26.0.0.0)
  Host Name:                    fsfovm3
  Last Ping to Primary:         6 seconds ago
  Log File:                     /home/oracle/observerz3.log
  State File:                   /home/oracle/observerz3.dat

为配置启用快速启动故障转移。

DGMGRL> enable fast_start failover
Enabled in Zero Data Loss Mode.

验证观察程序和配置状态是否显示 "Fast-Start Failover" 为 "Enabled"。

DGMGRL> show observer
Configuration - db26_dgconf
  Fast-Start Failover:     ENABLED
  Primary:            DBzone1
  Active Target:      DBzone2
Observer "observer3"(23.26.0.0.0) - Master
  Host Name:                    fsfovm3
  Last Ping to Primary:         1 second ago
  Last Ping to Target:          2 seconds ago
  Log File:                     /home/oracle/observerz3.log
  State File:                   /home/oracle/observerz3.dat

DGMGRL> show configuration
Configuration - db26_dgconf
  Protection Mode: MaxAvailability
  Members:
  DBzone1 - Primary database
    DBzone2 - (*) Physical standby database
Fast-Start Failover: Enabled in Zero Data Loss Mode
Configuration Status:
SUCCESS   (status updated 13 second ago)

DGMGRL> show fast_start failover
Fast-Start Failover: Enabled in Zero Data Loss Mode
...

观察程序正在运行，并且为 Data Guard 配置启用了快速启动故障转移。