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Manual hot backup

Shulou Source: shulou.com Published: 2022-06-01 16:14:15 09月10日 Update

Manual hot backup steps:

Open backup is only used in archive mode, and before hot backup, execute the command:

Hot standby steps:

alter database/tablespace XXX begin backup This sentence causes the lock block header to change, and the scn sign does not change.

cp files

alter database/tablespace XXX end backup

Experiment with backing up users tablespaces and testing deleted files and restores:

First, start backing up the users table space.

sys@TEST0910> alter tablespace users begin backup;

Tablespace altered.

2, the operating system command copy file:

[oracle@rtest ~]$ cd /u01/app/oracle

[oracle@rtest oracle]$ mkdir hot_dir

[oracle@rtest oracle]$ cp /u01/app/oracle/oradata/test0910/users01.dbf /u01/app/oracle/hot_dir/users01.dbf

3. End the backup of the users table space:

sys@TEST0910> alter tablespace users end backup;

Tablespace altered.

4. Delete users01.dbf file at this time

[oracle@rtest oracle]$ ls /u01/app/oracle/oradata/test0910/users01.dbf

ls: /u01/app/oracle/oradata/test0910/users01.dbf: No such file or directory

5. Close the library, reopen the library, and report an error:

sys@TEST0910> shutdown immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

sys@TEST0910> startup

ORACLE instance started.

Total System Global Area 2505338880 bytes

Fixed Size 2230952 bytes

Variable Size 587203928 bytes

Database Buffers 1895825408 bytes

Redo Buffers 20078592 bytes

Database mounted.

ORA-01157: cannot identify/lock data file 4 - see DBWR trace file

ORA-01110: data file 4: '/u01/app/oracle/oradata/test0910/users01.dbf'

6, copy to the correct location through the operating system,(can also be restored through rman, here in copy mode)

[oracle@rtest oracle]$ cp /u01/app/oracle/hot_dir/users01.dbf /u01/app/oracle/oradata/test0910/users01.dbf

[oracle@rtest oracle]$ ls /u01/app/oracle/oradata/test0910/users01.dbf

/u01/app/oracle/oradata/test0910/users01.dbf

7. Open the library again, report error, need media recovery:

sys@TEST0910> alter database open;

alter database open

*

ERROR at line 1:

ORA-01113: file 4 needs media recovery

ORA-01110: data file 4: '/u01/app/oracle/oradata/test0910/users01.dbf'

8. Media recovery:

sys@TEST0910> recover datafile 4;

Media recovery complete.

9. Re-open the library. Success:

sys@TEST0910> alter database open;

Database altered.