1.确定增量恢复起点SCN
有如下方法:
-
备库查看丢失的归档序列号
--备库查看丢失的归档号 SELECT * FROM V$ARCHIVE_GAP; --主库执行,查看SCN,146为第一个缺失归档的序列号 SELECT FIRST_CHANGE# FROM V$ARCHIVED_LOG WHERE SEQUENCE#=146;
-
备库查看当前的SCN
SELECT TO_CHAR(CURRENT_SCN) FROM V$DATABASE;
-
备库查看文件的SCN
SELECT DISTINCT CHECKPOINT_CHANGE# FROM V$DATAFILE_HEADER;
在测试环境中,以上CURRENT_SCN为5156981,其他两个都为5156982
2.增量备份
2.1.主库执行增量备份
run{
allocate channel d1 type disk;
allocate channel d2 type disk;
backup as compressed backupset incremental from SCN 5156981 database format ‘/archlog/backup/standby_%d_%T_%U.bak‘ tag ‘FOR STANDBY‘;
backup current controlfile for standby format ‘/archlog/backup/standby_%d_%T_%U_CTRL.bak‘;
release channel d1;
release channel d2;
}
2.2.传送到备库
scp * xxx.xxx.xxx.xxx:/archlog/backup/
3.备库恢复
3.1.恢复控制文件
数据库至nomount状态
alter database recover managed standby database cancel;
shutdown immediate;
startup nomount;
进入rman恢复
restore standby controlfile from ‘/archlog/backup/standby_DGTEST_20210621_0d01vmh7_1_1_CTRL.bak‘;
3.2.识别增量备份
数据库至mount状态
alter database mount;
识别备份
catalog start with ‘/archlog/backup‘;
3.3.查找新增的文件
如果没有新增文件,可以忽略此节
3.3.1.查找文件
SELECT * FROM V$DATAFILE_HEADER WHERE CREATION_CHANGE#>5156981;
3.3.2.修改备库参数
alter system set standby_file_management = manual;
3.3.3.新增对应的文件
SELECT ‘alter database create datafile ‘‘‘||name||‘‘‘;‘ FROM V$DATAFILE_HEADER WHERE CREATION_CHANGE#>5156981;
3.3.4.修改备库参数
alter system set standby_file_management = auto;
3.4.恢复备库
recover database noredo
4.开启数据库日志应用
alter database open read only;
alter database recover managed standby database disconnect;
5.测试并开启全备
主库新建一个表查看备库是否OK