小知识：linux rm误删除数据库文件的恢复方法

1.首先测试rm 误删除数据库文件  [oracle@primary dbwdn]$ ll  total 2153164  –rw-r—– 1 oracle dba 8536064 Nov 27 21:50 control01.ctl  -rw-r—– 1 oracle dba 8536064 Nov 27 21:50 control02.ctl  -rw-r—– 1 oracle dba 8536064 Nov 27 21:50 control03.ctl  -rw-r—– 1 oracle dba 104865792 Nov 27 21:32 ggs01.dbf  -rw-r—– 1 oracle dba 525344768 Nov 27 21:32 perfstat.dbf  -rw-r—– 1 oracle dba 52429312 Nov 27 21:10 redo01.log  -rw-r—– 1 oracle dba 52429312 Nov 27 21:49 redo02.log  -rw-r—– 1 oracle dba 52429312 Nov 27 21:10 redo03.log  -rw-r—– 1 oracle dba 10493952 Nov 27 21:32 shkz_data_01.dbf  -rw-r—– 1 oracle dba 524296192 Nov 27 21:49 sysaux01.dbf  -rw-r—– 1 oracle dba 524296192 Nov 27 21:49 system01.dbf  -rw-r—– 1 oracle dba 209723392 Nov 18 10:54 temp01.dbf  -rw-r—– 1 oracle dba 52436992 Nov 27 21:32 test01.dbf  -rw-r—– 1 oracle dba 251666432 Nov 27 21:49 undotbs01.dbf  -rw-r—– 1 oracle dba 26222592 Nov 27 21:32 users01.dbf  [oracle@primary dbwdn]$ rm test01.dbf  2.找到数据库后台进程dbw0  oracle 3493 1 0 21:10 ? 00:00:00 ora_dbw0_dbwdn  进程号3493  3.找到被误删除的数据库文件  [oracle@primary dbwdn]$ ll /proc/3493/fd  total 0  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 0 -> /dev/null  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 1 -> /dev/null  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 10 -> /dev/zero  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 11 -> /dev/zero  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 12 -> /u01/app/oracle/product/10.2.0/db_1/rdbms/mesg/oraus.msb  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 13 -> /u01/app/oracle/product/10.2.0/db_1/dbs/hc_dbwdn.dat  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 14 -> /u01/app/oracle/product/10.2.0/db_1/dbs/lkDBWDN  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 15 -> /u01/app/oracle/oradata/dbwdn/control01.ctl  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 16 -> /u01/app/oracle/oradata/dbwdn/control02.ctl  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 17 -> /u01/app/oracle/oradata/dbwdn/control03.ctl  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 18 -> /u01/app/oracle/oradata/dbwdn/system01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 19 -> /u01/app/oracle/oradata/dbwdn/undotbs01.dbf  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 2 -> /dev/null  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 20 -> /u01/app/oracle/oradata/dbwdn/sysaux01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 21 -> /u01/app/oracle/oradata/dbwdn/users01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 22 -> /u01/app/oracle/oradata/dbwdn/test01.dbf (deleted)  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 23 -> /u01/app/oracle/oradata/dbwdn/ggs01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 24 -> /u01/app/oracle/oradata/dbwdn/perfstat.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 25 -> /u01/app/oracle/oradata/dbwdn/shkz_data_01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 26 -> /u01/app/oracle/oradata/dbwdn/temp01.dbf  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 27 -> /u01/app/oracle/product/10.2.0/db_1/rdbms/mesg/oraus.msb  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 3 -> /dev/null  lr-x—— 1 oracle oinstall 64 Nov 27 21:52 4 -> /dev/null  l-wx—— 1 oracle oinstall 64 Nov 27 21:52 5 -> /u01/app/oracle/admin/dbwdn/udump/dbwdn_ora_3485.trc  l-wx—— 1 oracle oinstall 64 Nov 27 21:52 6 -> /u01/app/oracle/admin/dbwdn/bdump/alert_dbwdn.log  lrwx—— 1 oracle oinstall 64 Nov 27 21:52 7 -> /u01/app/oracle/product/10.2.0/db_1/dbs/hc_dbwdn.dat  l-wx—— 1 oracle oinstall 64 Nov 27 21:52 8 -> /u01/app/oracle/admin/dbwdn/bdump/alert_dbwdn.log  误删除之后，数据库没有重启，系统也没用重启  4.拷贝数据库文件  [oracle@primary ~]$ cp /proc/3493/fd/22 /u01/app/oracle/oradata/dbwdn/test01.dbf  [oracle@primary ~]$ cd /u01/app/oracle/oradata/dbwdn  [oracle@primary dbwdn]$ ls  control01.ctl control03.ctl perfstat.dbf redo02.log shkz_data_01.dbf system01.dbf test01.dbf users01.dbf  control02.ctl ggs01.dbf redo01.log redo03.log sysaux01.dbf temp01.dbf undotbs01.dbf  数据库文件找回来了。  5.恢复数据库文件  [oracle@primary dbwdn]$ sqlplus “/as sysdba”  SQL*Plus: Release 10.2.0.5.0 – Production on Tue Nov 27 21:55:15 2012  Copyright (c) 1982, 2010, Oracle. All Rights Reserved.  Connected to:  Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 – Production  With the Partitioning, OLAP, Data Mining and Real Application Testing options  SQL> alter database datafile 5 offline;  Database altered.  SQL> recover datafile 5;  Media recovery complete.  SQL> alter database datafile 5 online;  Database altered.  SQL> shutdown immediate;  Database closed.  Database dismounted.  ORACLE instance shut down.  SQL> startup  ORACLE instance started.  Total System Global Area 285212672 bytes  Fixed Size 1273276 bytes  Variable Size 130024004 bytes  Database Buffers 150994944 bytes  Redo Buffers 2920448 bytes  Database mounted.  Database opened.  SQL>  成功恢复数据库  注：如果数据库重启之后，还能恢复吗，测试一下：  [oracle@primary dbwdn]$ rm users01.dbf[oracle@primary dbwdn]$ ps -ef |grep dbw0  oracle 3798 1 0 21:56 ? 00:00:00 ora_dbw0_dbwdn  oracle 4147 3439 0 22:07 pts/1 00:00:00 grep dbw0  [oracle@primary dbwdn]$ ll /proc/3798/fd  total 0  lr-x—— 1 oracle oinstall 64 Nov 27 22:07 0 -> /dev/null  lr-x—— 1 oracle oinstall 64 Nov 27 22:07 1 -> /dev/null  lr-x—— 1 oracle oinstall 64 Nov 27 22:07 10 -> /dev/zero  lr-x—— 1 oracle oinstall 64 Nov 27 22:07 11 -> /dev/zero  lr-x—— 1 oracle oinstall 64 Nov 27 22:07 12 -> /u01/app/oracle/product/10.2.0/db_1/rdbms/mesg/oraus.msb  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 13 -> /u01/app/oracle/product/10.2.0/db_1/dbs/hc_dbwdn.dat  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 14 -> /u01/app/oracle/product/10.2.0/db_1/dbs/lkDBWDN  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 15 -> /u01/app/oracle/oradata/dbwdn/control01.ctl  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 16 -> /u01/app/oracle/oradata/dbwdn/control02.ctl  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 17 -> /u01/app/oracle/oradata/dbwdn/control03.ctl  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 18 -> /u01/app/oracle/oradata/dbwdn/system01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 19 -> /u01/app/oracle/oradata/dbwdn/undotbs01.dbf  lr-x—— 1 oracle oinstall 64 Nov 27 22:07 2 -> /dev/null  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 20 -> /u01/app/oracle/oradata/dbwdn/sysaux01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 21 -> /u01/app/oracle/oradata/dbwdn/users01.dbf (deleted)lrwx—— 1 oracle oinstall 64 Nov 27 22:07 22 -> /u01/app/oracle/oradata/dbwdn/test01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 23 -> /u01/app/oracle/oradata/dbwdn/ggs01.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 24 -> /u01/app/oracle/oradata/dbwdn/perfstat.dbf  lrwx—— 1 oracle oinstall 64 Nov 27 22:07 25 -> /u01/app/oracle/oradata/dbwdn/shkz_data_01.dbf  数据库没有重启，这个数据文件还能恢复，如果我重启数据库之后，还能看见这个数据文件吗？  [oracle@primary dbwdn]$ sqlplus “/as sysdba”  SQL*Plus: Release 10.2.0.5.0 – Production on Tue Nov 27 22:08:01 2012  Copyright (c) 1982, 2010, Oracle. All Rights Reserved.  Connected to:  Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 – Production  With the Partitioning, OLAP, Data Mining and Real Application Testing options  SQL> shutdown immediate;  ORA-01116: error in opening database file 4  ORA-01110: data file 4: /u01/app/oracle/oradata/dbwdn/users01.dbf  ORA-27041: unable to open file  Linux Error: 2: No such file or directory  Additional information: 3  SQL> shutdown abort;ORACLE instance shut down.  SQL> exit  Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 – Production  With the Partitioning, OLAP, Data Mining and Real Application Testing options  [oracle@primary dbwdn]$ sqlplus “/as sysdba”  SQL*Plus: Release 10.2.0.5.0 – Production on Tue Nov 27 22:08:19 2012  Copyright (c) 1982, 2010, Oracle. All Rights Reserved.  Connected to an idle instance.  SQL> startup  ORACLE instance started.  Total System Global Area 285212672 bytes  Fixed Size 1273276 bytes  Variable Size 130024004 bytes  Database Buffers 150994944 bytes  Redo Buffers 2920448 bytes  Database mounted.  ORA-01157: cannot identify/lock data file 4 – see DBWR trace file  ORA-01110: data file 4: /u01/app/oracle/oradata/dbwdn/users01.dbf  SQL> exit  Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 – Production  With the Partitioning, OLAP, Data Mining and Real Application Testing options  [oracle@primary dbwdn]$ ll /proc/3798/fd  ls: /proc/3798/fd: No such file or directory  [oracle@primary dbwdn]$ ps -ef |grep dbw0  oracle 4160 1 0 22:08 ? 00:00:00 ora_dbw0_dbwdn  oracle 4193 3439 0 22:09 pts/1 00:00:00 grep dbw0  [oracle@primary dbwdn]$ ll /proc/4160/fd  total 0  lr-x—— 1 oracle oinstall 64 Nov 27 22:09 0 -> /dev/null  lr-x—— 1 oracle oinstall 64 Nov 27 22:09 1 -> /dev/null  lr-x—— 1 oracle oinstall 64 Nov 27 22:09 10 -> /dev/zero  lr-x—— 1 oracle oinstall 64 Nov 27 22:09 11 -> /dev/zero  lr-x—— 1 oracle oinstall 64 Nov 27 22:09 12 -> /u01/app/oracle/product/10.2.0/db_1/rdbms/mesg/oraus.msb  lrwx—— 1 oracle oinstall 64 Nov 27 22:09 13 -> /u01/app/oracle/product/10.2.0/db_1/dbs/hc_dbwdn.dat  lrwx—— 1 oracle oinstall 64 Nov 27 22:09 14 -> /u01/app/oracle/product/10.2.0/db_1/dbs/lkDBWDN  lrwx—— 1 oracle oinstall 64 Nov 27 22:09 15 -> /u01/app/oracle/oradata/dbwdn/control01.ctl  lrwx—— 1 oracle oinstall 64 Nov 27 22:09 16 -> /u01/app/oracle/oradata/dbwdn/control02.ctl  lrwx—— 1 oracle oinstall 64 Nov 27 22:09 17 -> /u01/app/oracle/oradata/dbwdn/control03.ctl  l-wx—— 1 oracle oinstall 64 Nov 27 22:09 2 -> /u01/app/oracle/admin/dbwdn/bdump/dbwdn_dbw0_4160.trc  lr-x—— 1 oracle oinstall 64 Nov 27 22:09 3 -> /dev/null  lr-x—— 1 oracle oinstall 64 Nov 27 22:09 4 -> /dev/null  l-wx—— 1 oracle oinstall 64 Nov 27 22:09 5 -> /u01/app/oracle/admin/dbwdn/udump/dbwdn_ora_4152.trc  l-wx—— 1 oracle oinstall 64 Nov 27 22:09 6 -> /u01/app/oracle/admin/dbwdn/bdump/alert_dbwdn.log  lrwx—— 1 oracle oinstall 64 Nov 27 22:09 7 -> /u01/app/oracle/product/10.2.0/db_1/dbs/hc_dbwdn.dat  l-wx—— 1 oracle oinstall 64 Nov 27 22:09 8 -> /u01/app/oracle/admin/dbwdn/bdump/alert_dbwdn.log  lrwx—— 1 oracle oinstall 64 Nov 27 22:09 9 -> /u01/app/oracle/product/10.2.0/db_1/dbs/lkinstdbwdn (deleted)  [oracle@primary dbwdn]$  已经没法恢复了。  说明需要注意的是，rm误删除文件之后，千万不要慌张，稳住神，不要重启数据库，不要重启动系统。  AIX系统，我没有测试过。  使用备份集恢复上面的数据库文件：  [oracle@primary dbwdn]$ rman target /  Recovery Manager: Release 10.2.0.5.0 – Production on Tue Nov 27 22:13:45 2012  Copyright (c) 1982, 2007, Oracle. All rights reserved.  connected to target database (not started)  RMAN> startup nomount;  Oracle instance started  Total System Global Area 285212672 bytes  Fixed Size 1273276 bytes  Variable Size 130024004 bytes  Database Buffers 150994944 bytes  Redo Buffers 2920448 bytes  RMAN> alter database mount;  using target database control file instead of recovery catalog  database mounted  RMAN> run  2> {  3> allocate channel t1 type to disk;  RMAN-00571: ===========================================================  RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============  RMAN-00571: ===========================================================  RMAN-00558: error encountered while parsing input commands  RMAN-01009: syntax error: found “to”: expecting one of: “double-quoted-string, disk, equal, identifier, single-quoted-string”  RMAN-01007: at line 3 column 26 file: standard input  RMAN> run  2> {  3> allocate channel t1 device type disk;  4> restore datafile 4;  5> recover datafile 4;  6> release channel t1;  7> }  allocated channel: t1  channel t1: sid=156 devtype=DISK  Starting restore at 27-NOV-2012 22:16:26  channel t1: starting datafile backupset restore  channel t1: specifying datafile(s) to restore from backup set  restoring datafile 00004 to /u01/app/oracle/oradata/dbwdn/users01.dbf  channel t1: reading from backup piece /u01/bak/03nrctnp_1_1.bak  channel t1: restored backup piece 1  piece handle=/u01/bak/03nrctnp_1_1.bak tag=TAG20121127T213241  channel t1: restore complete, elapsed time: 00:00:04  Finished restore at 27-NOV-2012 22:16:30  Starting recover at 27-NOV-2012 22:16:30  starting media recovery  media recovery complete, elapsed time: 00:00:01  Finished recover at 27-NOV-2012 22:16:31  released channel: t1  RMAN> alter database open;  database opened  RMAN>  Windows下数据恢复（把回收站清空后的恢复方法）：  步骤：  1、单击“开始——运行，然后输入regedit （打开注册表）  2、依次展开：HEKEY——LOCAL——MACHIME/SOFTWARE/microsoft/WINDOWS/ CURRENTVERSION/EXPLORER/DESKTOP/NAMESPACE 在左边空白外点击“新建”  ，选择：“主键”，把它命名为“645FFO40——5081——101B——9F08——00AA002F954E”  再把右边的“默认”的主键的键值设为“回收站”，然后退出注册表。就OK啦。  3、要重启计算机。  只要机器没有运行过磁盘整理。系统完好.任何时候的文件都可以找回来。