合 DG日常维护
Tags: Oracle
第一部分 日常维护
一 正确打开主库和备库
1 主库:
SQL> STARTUP MOUNT;
SQL> ALTER DATABASE ARCHIVELOG;
SQL> ALTER DATABASE OPEN;
2 备库:
SQL> STARTUP MOUNT;
SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION;
二 正确关闭顺序
1 备库:
SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;
SQL>SHUTDOWN IMMEDIATE;
2 主库
SQL>SHUTDOWN IMMEDIATE; ---先于standby执行
三 备库Read-Only模式打开
当前主库正常OPEN状态
备库处于日志传送状态.
1 在备库停止日志传送
SQL> alter database recover managed standby database cancel;
2 备库Read-only模式打开
SQL> alter database open read only;
3 备库回到日志传送模式
SQL>alter database recover managed standby database disconnect from session;
Media recovery complete.
SQL> select status from v$instance;
STATUS
------------
MOUNTED
四 日志传送状态监控
1 主库察看当前日志状况
SQL> select sequence#,status from v$log;
SEQUENCE# STATUS
51 ACTIVE
52 CURRENT
50 INACTIVE
2 备库察看RFS(Remote File Service)接收日志情况和MRP应用日志同步主库情况
SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;
PROCESS STATUS THREAD# SEQUENCE# BLOCK# BLOCKS
ARCH CONNECTED 0 0 0 0
ARCH CONNECTED 0 0 0 0
RFS RECEIVING 0 0 0 0
MRP0 WAIT_FOR_LOG 1 52 0 0
RFS RECEIVING 0 0 0 0
可以看到备库MPR0正等待SEQUENCE#为52的redo.
3 察看备库是否和主库同步
SQL> SELECT ARCHIVED_THREAD#, ARCHIVED_SEQ#, APPLIED_THREAD#, APPLIED_SEQ# FROM V$ARCHIVE_DEST_STATUS;
ARCHIVED_THREAD# ARCHIVED_SEQ# APPLIED_THREAD# APPLIED_SEQ#
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
1 51 1 50
可以看到备库已经将SEQUENCE#51的日志归档,已经将SEQUENCE#50的redo应用到备库.
由于已经将SEQUENCE#51的日志归档,所以SEQUENCE#51以前的数据不会丢失.
4 察看备库已经归档的redo
SQL> SELECT REGISTRAR, CREATOR, THREAD#, SEQUENCE#, FIRST_CHANGE#,NEXT_CHANGE# FROM V$ARCHIVED_LOG;
REGISTR CREATOR THREAD# SEQUENCE# FIRST_CHANGE# NEXT_CHANGE#
SRMN SRMN 1 37 572907 573346
RFS ARCH 1 38 573346 573538
RFS ARCH 1 39 573538 573623
RFS ARCH 1 40 573623 573627
RFS ARCH 1 41 573627 574326
RFS ARCH 1 42 574326 574480
RFS ARCH 1 43 574480 590971
RFS ARCH 1 44 590971 593948
RFS FGRD 1 45 593948 595131
RFS FGRD 1 46 595131 595471
FGRD FGRD 1 46 595131 595471
REGISTR CREATOR THREAD# SEQUENCE# FIRST_CHANGE# NEXT_CHANGE#
RFS ARCH 1 47 595471 595731
RFS ARCH 1 48 595731 601476
RFS ARCH 1 49 601476 601532