12C新特性:Far Sync Instance
Oracle 12C Data Guard中引入一个新特性Active Data Guard Far Sync,也称为Far Sync Standby。它不包含任何数据文件,只包含一些必要的文件,如:控制文件,spfile和standby redo logfile。 Far Sync Standby只运行日志传输服务。
配置Far Sync 实例
主库上创建控制文件和spfile
sqlplus "/ as sysdba"<<EOF
alter database create far sync instance controlfile as '/tmp/far_sync.ctl';
create pfile='/tmp/init.ora' from spfile;
EOF
传输文件到Far Sync端
scp /tmp/far_sync.ctl /tmp/init.ora oracle@node2:/tmp/
创建相关目录
修改spfile文件
vi /tmp/init.ora
LOG_ARCHIVE_CONFIG ='DG_CONFIG=(primary,farsync,standby)'
LOG_ARCHIVE_DEST_1='location=USE_DB_RECOVERY_FILE_DEST, valid_for=(STANDBY_LOGFILE,STANDBY_ROLE)'
LOG_ARCHIVE_DEST_2='SERVICE=tns_standby LGWR ASYNC NOAFFIRM delay=0 optional compression=disable max_failure=0 max_connections=1 reopen=300 VALID_FOR=(STANDBY_LOGFILES,STANDBY_ROLE) DB_UNIQUE_NAME=standby'
创建far sync实例并启动mount
sqlplus "/ as sysdba"<<EOF
create spfile from pfile='/tmp/init.or';
startup mount;
select protection_mode,database_role,protection_level,open_mode from v$database;
-- 创建SRL
alter database add standby logfile thread 1 group 20 '+SRL' size 1024M;
alter database add standby logfile thread 1 group 21 '+SRL' size 1024M;
alter database add standby logfile thread 1 group 22 '+SRL' size 1024M;
set linesize 300
col member for a100
select GROUP#,MEMBER,TYPE from v$logfile;
EOF