环境描述
| 角色 | IP地址 | hostsname | DB_unique_name | 实例名 | 监听服务 | 控制文件 |
|---|---|---|---|---|---|---|
| 主库 | 192.168.10.91 | primary-database | orcl | orcl | Listener | /u01/app/oracle/oradata/orcl/control01.ctl,/u01/app/oracle/fast_recovery_area/orcl/control02.ctl |
| 备库 | 192.168.10.94 | standby-dtabase | orcl | orcl | Listener | |
| far_sync_01 | 192.168.10.92 | far-snyc-01 | orcl | orcl | Listener | |
| far_sync_02 | 192.168.10.93 | far-sync-02 | orcl | orcl | Listener |
本次实验的构架:

在 Oracle DG 中,从主库到备库的日志传输有sync和async两种方式,sync的方式能够实现数据实时传输,但如果遇到网络中断等原因,就可能导致数据丢失。因此,在Oracle 12c中提出了 Far Sync instance 的解决方案,事实上是一种零数据丢失的同步机制。
部署 ADG
FAR SYNC的两台服务器的话直接克隆的备库主机,克隆后删除数据文件即可;重新搭建的话只需要ORACLE软件,不需要建立数据库
http://bytesystem.online/doc/2564/
部署 far sysnc
主库创建控制文件
step 1.创建控制文件
SYS@primary> alter database create far sync instance controlfile as '/home/oracle/fs01.ctl';
Database altered.
SYS@primary>
step 2.创建 pfile 文件
SYS@primary> create pfile='/home/oracle/initorcl.ora' from spfile;
File created.
SYS@primary>
拷贝文件
传输控制文件,pfile,密码文件文件到 Far Sync instance 节点
scp /u01/app/oracle/product/19.3.0/dbhome_1/dbs/orapworcl oracle@192.168.10.93:/u01/app/oracle/product/19.3.0/dbhome_1/dbs/
scp /u01/app/oracle/product/19.3.0/dbhome_1/dbs/initorcl.ora oracle@192.168.10.93:/u01/app/oracle/product/19.3.0/dbhome_1/dbs/
scp /home/oracle/fs01.ctl oracle@192.168.10.93:/u01/app/oracle/product/19.3.0/dbhome_1/dbs/
主库部署
step 1.编辑 tnsnames.ora
# tnsnames.ora Network Configuration File: /u01/app/oracle/product/19.3.0/dbhome_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
LISTENER_ORCL =
(ADDRESS = (PROTOCOL = TCP)(HOST = primary-database)(PORT = 1521))
PRIMARY =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = primary-database)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
STANDBY =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = standby-database)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
FARSYNC01 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-01)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
FARSYNC02 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-02)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
step 2.配置 DB_UNIQUE_NAME
alter system set db_unique_name='primary';
step 3.配置 FAL_SERVER
alter system set fal_server='standby';
alter system set fal_client='primary';
fal_server的值写的是tnsname中的服务名,这里主库上设置的fs的服务名是小写的就小写
step 4.配置 LOG_ARCHIVE_CONFIG
alter system set log_archive_config='dg_config=(primary,farsync01,farsync02,standby)';
dg_config是写db_unique_name的值。
step 5.配置 log_archive_dest
LOG_ARCHIVE_DEST_1 指向本地归档路径
alter system set LOG_ARCHIVE_DEST_1='LOCATION=/u01/app/oracle/archivelog VALID_FOR=(online_logfile,primary_role) DB_UNIQUE_NAME=orcl';
LOG_ARCHIVE_DEST_2 指向fs1机器,使用sync
# farsync01
alter system set log_archive_dest_2='service=FARSYNC01 lgwr SYNC affirm max_failure=1 alternate=log_archive_dest_2 VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=farsync01';
LOG_ARCHIVE_DEST_3 指向fs2机器,使用sync
# farsync02
alter system set log_archive_dest_3='service=FARSYNC02 lgwr ASYNC alternate=log_archive_dest_3 VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=farsync02';
配置 Far Sync 1 实例
FarSync 实例添加 standby log,该配置已经在DG环境中添加。无需重复操作。
step 1.配置 FarSync 实例的 tnsnames
# tnsnames.ora Network Configuration File: /u01/app/oracle/product/19.3.0/dbhome_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
LISTENER_ORCL =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-01)(PORT = 1521))
PRIMARY =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = primary-database)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
STANDBY =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = standby-database)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
FARSYNC01 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-01)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
FARSYNC02 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-02)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
step 2.创建相应的文件目录
mkdir -p /u01/app/oracle/archivelog
mkdir -p /u01/app/oracle/fast_recovery_area/orcl
mkdir -p /u01/app/oracle/admin/orcl/adump
mkdir -p /u01/app/oracle/oradata/orcl
step 3.启动到 nomount
SQL> startup nomount
step 4.配置 DB_UNIQUE_NAME
alter system set db_unique_name='farsync01';
step 5.配置 FAL_SERVER
alter system set fal_server='primary,standby';
alter system set fal_client='farsync01';
step 6.配置log_archive_config
alter system set log_archive_config='dg_config=(primary,farsync01,farsync02,standby)';
step 7.配置 log_archive_dest_n
log_archive_dest_1,写归档到本地归档路径
alter system set LOG_ARCHIVE_DEST_1='LOCATION=/u01/app/oracle/archivelog VALID_FOR=(ALL_LOGFILES,ALL_ROLES) DB_UNIQUE_NAME=orcl';
log_archive_dest_2,写归档到备库,用async的方式,因为主到fs是sync,fs到备库是async。
- 当主库归档写到 fs1 ,fs1 传送到备库; fs1 故障不可用时,归档写入到fs2
alter system set log_archive_dest_2='service=STANDBY async valid_for=(standby_logfiles,standby_role) db_unique_name=standby';
- 当备库归档写到 fs1 ,fs1 传送到备库; fs1 故障不可用时,归档写入到fs2
alter system set log_archive_dest_3='service=PRIMARY async valid_for=(standby_logfiles,standby_role) db_unique_name=primary';
step 8.恢复控制文件
[oracle@far-sync-01 dbs]$ rman target /
Recovery Manager: Release 19.0.0.0.0 - Production on Sun Apr 28 11:37:24 2024
Version 19.3.0.0.0
Copyright (c) 1982, 2019, Oracle and/or its affiliates. All rights reserved.
connected to target database: ORCL (not mounted)
RMAN> restore controlfile from '/u01/app/oracle/product/19.3.0/dbhome_1/dbs/fs01.ctl';
Starting restore at 2024-04-28 11:38:17
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=261 device type=DISK
channel ORA_DISK_1: copied control file copy
output file name=/u01/app/oracle/oradata/ORCL/control01.ctl
output file name=/u01/app/oracle/oradata/ORCL/control02.ctl
Finished restore at 2024-04-28 11:38:21
RMAN>
step 9.在 Far Sync 实例服务器创建监听器(过程略)。
step 10.启动到 mount
SQL> alter database mount;
恢复后再后续的启动中就只需要启动到 mount 状态即可
step 11.创建standby redo log
在Far Sync实例创建standby redo log,standby redo log大小等于主库online redo log大小:
alter database drop standby logfile group 4;
alter database drop standby logfile group 5;
alter database drop standby logfile group 6;
alter database drop standby logfile group 7;
alter database add standby logfile group 8 '/u01/app/oracle/oradata/ORCL/STANDBY_REDO08.LOG' size 200M;
alter database add standby logfile group 9 '/u01/app/oracle/oradata/ORCL/STANDBY_REDO09.LOG' size 200M;
alter database add standby logfile group 10 '/u01/app/oracle/oradata/ORCL/STANDBY_REDO10.LOG' size 200M;
alter database add standby logfile group 11 '/u01/app/oracle/oradata/ORCL/STANDBY_REDO11.LOG' size 200M;
配置 Far Sync 2 实例
FarSync 实例添加 standby log,该配置已经在DG环境中添加。无需重复操作。
step 1.配置 FarSync 实例的 tnsnames
# tnsnames.ora Network Configuration File: /u01/app/oracle/product/19.3.0/dbhome_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
LISTENER_ORCL =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-01)(PORT = 1521))
PRIMARY =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = primary-database)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
STANDBY =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = standby-database)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
FARSYNC01 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-01)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
FARSYNC02 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-02)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
step 2.创建相应的文件目录
mkdir -p /u01/app/oracle/archivelog
mkdir -p /u01/app/oracle/fast_recovery_area/orcl
mkdir -p /u01/app/oracle/admin/orcl/adump
mkdir -p /u01/app/oracle/oradata/orcl
step 3.启动到 nomount
SQL> startup nomount
step 4.配置 DB_UNIQUE_NAME
alter system set db_unique_name='farsync02';
step 5.配置 FAL_SERVER
alter system set fal_server='primary,standby';
alter system set fal_client='farsync02';
step 6.配置log_archive_config
alter system set log_archive_config='dg_config=(primary,farsync01,farsync02,standby)';
step 7.配置 log_archive_dest_n
log_archive_dest_1,写归档到本地归档路径
alter system set LOG_ARCHIVE_DEST_1='LOCATION=/u01/app/oracle/archivelog VALID_FOR=(ALL_LOGFILES,ALL_ROLES) DB_UNIQUE_NAME=orcl';
log_archive_dest_2,写归档到备库,用async的方式,因为主到fs是sync,fs到备库是async。
- 当主库归档写到 fs2 ,fs2 传送到备库; fs2 故障不可用时,归档写入到fs1
alter system set log_archive_dest_2='service=STANDBY async valid_for=(standby_logfiles,standby_role) db_unique_name=standby';
- 当备库归档写到 fs1 ,fs1 传送到备库; fs1 故障不可用时,归档写入到fs2
alter system set log_archive_dest_3='service=PRIMARY async valid_for=(standby_logfiles,standby_role) db_unique_name=primary';
step 8.恢复控制文件
[oracle@far-sync-01 dbs]$ rman target /
Recovery Manager: Release 19.0.0.0.0 - Production on Sun Apr 28 11:37:24 2024
Version 19.3.0.0.0
Copyright (c) 1982, 2019, Oracle and/or its affiliates. All rights reserved.
connected to target database: ORCL (not mounted)
RMAN> restore controlfile from '/u01/app/oracle/product/19.3.0/dbhome_1/dbs/fs01.ctl';
Starting restore at 2024-04-28 11:38:17
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=261 device type=DISK
channel ORA_DISK_1: copied control file copy
output file name=/u01/app/oracle/oradata/ORCL/control01.ctl
output file name=/u01/app/oracle/oradata/ORCL/control02.ctl
Finished restore at 2024-04-28 11:38:21
RMAN>
step 9.在 Far Sync 实例服务器创建监听器(过程略)。
step 10.启动到 mount
SQL> alter database mount;
恢复后再后续的启动中就只需要启动到 mount 状态即可
step 11.创建standby redo log
在Far Sync实例创建standby redo log,standby redo log大小等于主库online redo log大小:
alter database drop standby logfile group 4;
alter database drop standby logfile group 5;
alter database drop standby logfile group 6;
alter database drop standby logfile group 7;
alter database add standby logfile group 8 '/u01/app/oracle/oradata/ORCL/STANDBY_REDO08.LOG' size 200M;
alter database add standby logfile group 9 '/u01/app/oracle/oradata/ORCL/STANDBY_REDO09.LOG' size 200M;
alter database add standby logfile group 10 '/u01/app/oracle/oradata/ORCL/STANDBY_REDO10.LOG' size 200M;
alter database add standby logfile group 11 '/u01/app/oracle/oradata/ORCL/STANDBY_REDO11.LOG' size 200M;
备库配置
step 1.编辑 tnsnames.ora
# tnsnames.ora Network Configuration File: /u01/app/oracle/product/19.3.0/dbhome_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
LISTENER_ORCL =
(ADDRESS = (PROTOCOL = TCP)(HOST = standby-database)(PORT = 1521))
PRIMARY =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = primary-database)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
STANDBY =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = standby-database)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
FARSYNC01 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-01)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
FARSYNC02 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = far-sync-02)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
step 2.配置 DB_UNIQUE_NAME
alter system set db_unique_name='standby';
step 3.配置 FAL_SERVER
alter system set fal_server='primary';
alter system set fal_client='standby';
step 4.配置LOG_ARCHIVE_CONFIG
alter system set log_archive_config='dg_config=(primary,farsync01,farsync02,standby)';
dg_config是写db_unique_name的值。
step 5.配置 log_archive_dest
LOG_ARCHIVE_DEST_1 指向本地归档路径
alter system set LOG_ARCHIVE_DEST_1='LOCATION=/u01/app/oracle/archivelog VALID_FOR=(online_logfile,primary_role) DB_UNIQUE_NAME=orcl';
LOG_ARCHIVE_DEST_2 指向fs1机器,使用sync
# farsync01
alter system set log_archive_dest_2='service=FARSYNC01 lgwr SYNC affirm max_failure=1 alternate=log_archive_dest_2 VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=farsync01';
LOG_ARCHIVE_DEST_3 指向fs2机器,使用sync
# farsync02
alter system set log_archive_dest_3='service=FARSYNC02 lgwr ASYNC alternate=log_archive_dest_3 VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=farsync02';
检查配置情况
# 查看dataguard_config
select * from V$DATAGUARD_CONFIG;
# 查看同步情况
select * FROM V$DATAGUARD_STATS;
select dest_id,status,error from v$archive_dest;
启动
step 1.关闭所有 FAR 服务的数据库
step 2.重启主库
SQL> shutdown immediate
SQL> startup
step 3.重启备库
SQL> shutdown immediate
SQL> startup
SQL> alter database recover managed standby database using current logfile disconnect from session;
step 4.启动FAR Sync 节点一
SQL> startup mount
step 5.启动FAR Sync 节点二
SQL> startup mount
主库查看保护级别
SQL> select open_mode,protection_mode,protection_level,switchover_status from v$database;
OPEN_MODE PROTECTION_MODE PROTECTION_LEVEL SWITCHOVER_STATUS
-------------------- -------------------- -------------------- --------------------
READ WRITE MAXIMUM PERFORMANCE MAXIMUM PERFORMANCE TO STANDBY
发现并不是最大可用模式,我们进行调整,语法:
SQL> alter database set standby database to maximize availability;
Database altered.
SQL> select open_mode,protection_mode,protection_level,switchover_status from v$database;
OPEN_MODE PROTECTION_MODE PROTECTION_LEVEL SWITCHOVER_STATUS
-------------------- -------------------- -------------------- --------------------
READ WRITE MAXIMUM AVAILABILITY MAXIMUM AVAILABILITY TO STANDBY
一个 Far Sync 实例,如果出现问题,虽然能够保证 redo 直接传输到 standby 库,但是 primary 库保护模式从最大可用模式(MaximumAvailability)降为最大性能模式(Maximum Performance)。 因此我们可以在距离主库较近的地点设置 2 个 FarSync 实例保证高可用性。当一个 Far Sync实例不可用, primary 库自动使用备用 FarSync 库,并且 primary 库保护模式保持最大可用模式(Maximum Availability) 不变,零数据丢失。
节点启动状态
主库查看命令:
set linesize 160
select * from v$dataguard_config;
理论上是未应用的那个unknown !! 状态的话主库认识到状态未FAR就会发送日志过去
查看Far Sync实例状态
select protection_mode,database_role,protection_level,open_mode from v$database;
查看日志有没有问题
手工切换日志,可在下方命令查询后切换此命令,再次查询,看是否由改变
alter system archive log current;
主库:
SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
279
far sync:
SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
279
备库:
SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
279
FARsync2:
SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
276 ---这个日志没有与他们一样是因为没有应用,FAR1 宕机后就会通过这个来应用




