Home Database Mysql Tutorial current online redo logfile 丢失的处理方法

current online redo logfile 丢失的处理方法

Jun 07, 2016 pm 04:43 PM

做了rm -rf操作后的恢复演练,而且是在没有任何备份的情况下。今天在做破坏性操作前,做了个rman全备,然后在线删除全部数据库文

前面(见)做了rm -rf操作后的恢复演练,而且是在没有任何备份的情况下。今天在做破坏性操作前,做了个rman全备,然后在线删除全部数据库文件,包括控制文件,数据文件,在线日志文件,归档文件等。来看看有什么方法可以让数据库恢复运行,由于是current redo logfile丢失,那么本次测试是会丢失数据的,所以可以作为不完全恢复的一个案例。 

--登入数据库进行dml操作
 [Oracle@ora10g ~]$ sqlplus / as sysdba
 

SQL*Plus: Release 10.2.0.1.0 - Production on Tue Aug 26 13:40:37 2014
 

Copyright (c) 1982, 2005, Oracle.  All rights reserved. 

Connected to:
 Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
 With the Partitioning, OLAP and Data Mining options
 

SQL> select * from aaron8219.test1;
 

      INT
 ----------
          1
          2
 

SQL> insert into aaron8219.test1 values(3);
 

1 row created.
 

SQL> select group#,status,sequence# from v$log;
 

    GROUP# STATUS              SEQUENCE#
 ---------- ---------------- ----------
          1 INACTIVE                  1
          2 CURRENT                2
          3 INACTIVE                  0
 

--不提交,另开一个session进行rm -rf操作
 [root@ora10g ~]# cd /u01/app/oracle/oradata
 [root@ora10g oradata]# ll
 total 4
 drwxr-x--- 2 oracle oinstall 4096 Aug 25 16:09 ora10g
 [root@ora10g oradata]# rm -rf ora10g/
 [root@ora10g oradata]# ll
 total 0
 

--原session直接abort关闭,模拟current online redo logfile丢失
 SQL> shutdown abort
 

--用之前刚生成的rman全备来还原数据库各类文件
 [oracle@ora10g ~]$ rman target /
 

Recovery Manager: Release 10.2.0.1.0 - Production on Tue Aug 26 13:44:58 2014
 

Copyright (c) 1982, 2005, Oracle.  All rights reserved.
 

connected to target database: ora10g (not mounted)
 

RMAN> restore controlfile from '/rmanbak/full_ORA10G_4175411955_20140826_02pgtq5h_1_1.bak';
 

Starting restore at 26-AUG-14
 using channel ORA_DISK_1
 

channel ORA_DISK_1: restoring control file
 channel ORA_DISK_1: restore complete, elapsed time: 00:00:04
 output filename=/u01/app/oracle/oradata/ora10g/control01.ctl
 output filename=/u01/app/oracle/oradata/ora10g/control02.ctl
 output filename=/u01/app/oracle/oradata/ora10g/control03.ctl
 Finished restore at 26-AUG-14
 

RMAN> alter database mount;
 

database mounted
 released channel: ORA_DISK_1
 

RMAN> restore database;
 

Starting restore at 26-AUG-14
 Starting implicit crosscheck backup at 26-AUG-14
 allocated channel: ORA_DISK_1
 channel ORA_DISK_1: sid=156 devtype=DISK
 Crosschecked 1 objects
 Finished implicit crosscheck backup at 26-AUG-14
 

Starting implicit crosscheck copy at 26-AUG-14
 using channel ORA_DISK_1
 Finished implicit crosscheck copy at 26-AUG-14
 

searching for all files in the recovery area
 cataloging files...
 cataloging done
 

List of Cataloged Files
 =======================
 File Name: /u01/app/oracle/flash_recovery_area/ORA10G/autobackup/2014_08_26/o1_mf_s_856615092_9zr3snsq_.bkp
 

using channel ORA_DISK_1
 

channel ORA_DISK_1: starting datafile backupset restore
 channel ORA_DISK_1: specifying datafile(s) to restore from backup set
 restoring datafile 00001 to /u01/app/oracle/oradata/ora10g/system01.dbf
 restoring datafile 00002 to /u01/app/oracle/oradata/ora10g/undotbs01.dbf
 restoring datafile 00003 to /u01/app/oracle/oradata/ora10g/sysaux01.dbf
 restoring datafile 00004 to /u01/app/oracle/oradata/ora10g/users01.dbf
 restoring datafile 00005 to /u01/app/oracle/oradata/ora10g/example01.dbf
 channel ORA_DISK_1: reading from backup piece /rmanbak/full_ORA10G_4175411955_20140826_01pgtq36_1_1.bak
 channel ORA_DISK_1: restored backup piece 1
 piece handle=/rmanbak/full_ORA10G_4175411955_20140826_01pgtq36_1_1.bak tag=TAG20140826T123653
 channel ORA_DISK_1: restore complete, elapsed time: 00:01:46
 Finished restore at 26-AUG-14
 

RMAN> exit
 


Recovery Manager complete.
 

由于rman并不备份在线日志文件,刚才的rman只是做了个全库备份和控制文件的备份,可以看到redo01.log,redo02.log,redo03.log这3个文件并不存在
 

[oracle@ora10g ~]$ sqlplus / as sysdba
 

SQL*Plus: Release 10.2.0.1.0 - Production on Tue Aug 26 14:52:35 2014
 

Copyright (c) 1982, 2005, Oracle.  All rights reserved.
 

 

Connected to:
 Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
 With the Partitioning, OLAP and Data Mining options
 

SQL> select open_mode from v$database;
 

OPEN_MODE
 ----------
 MOUNTED
 

SQL> col member for a60
 SQL> select group#,member from v$logfile;
 

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