控制檔案損壞處理

二、有 rman 備份的恢復

2.1 只損壞一個控制檔案的情況

本文件的恢復場景都是針對的多控制檔案的情況，如果你只有一個那當我沒說 😄 。

檢視控制檔案

SQL> show parameter control_files;
 
NAME                     TYPE     VALUE
------------------------------------ ----------- ------------------------------
control_files                 string     /oracle/app/oradata/orcl/control01.ctl, /oracle/app/oradata/orcl/control02.ctl

模擬破壞

[oracle@redhat11g8 orcl]$ echo ''>/oracle/app/oradata/orcl/control01.ctl

後臺日誌可以看到會報控制檔案有壞塊，但是例項還沒有宕：

Errors in file /oracle/app/diag/rdbms/orcl/orcl/trace/orcl_ckpt_30033.trc  (incident=38401):
ORA-00227: corrupt block detected in control file: (block 1, # blocks 1)
ORA-00202: control file: '/oracle/app/oradata/orcl/control01.ctl'

做一次檢查點切換：

SQL> alter system checkpoint;
alter system checkpoint
*
ERROR at line 1:
ORA-03113: end-of-file on communication channel
Process ID: 26789
Session ID: 153 Serial number: 2627

後臺日誌顯示例項被異常終止：

CKPT (ospid: 30033): terminating the instance due to error 227
Wed Feb 13 08:20:11 2019
System state dump requested by (instance=1, osid=30033 (CKPT)), summary=[abnormal instance termination].
System State dumped to trace file /oracle/app/diag/rdbms/orcl/orcl/trace/orcl_diag_30021_20190213082011.trc
Dumping diagnostic data in directory=[cdmp_20190213082011], requested by (instance=1, osid=30033 (CKPT)), summary=[abnormal instance termination].
Instance terminated by CKPT, pid = 30033

恢復方法：

cp control02.ctl control01.ctl

然後重新 startup 例項，執行正常。

2.2 所有控制檔案都損壞的情況

模擬破壞：

[oracle@redhat11g8 orcl]$ echo ''>control01.ctl
[oracle@redhat11g8 orcl]$ echo ''>control02.ctl
SQL> alter system checkpoint;
alter system checkpoint
*
ERROR at line 1:
ORA-03113: end-of-file on communication channel
Process ID: 26927
Session ID: 135 Serial number: 13

後臺日誌情況和前面一樣在發生檢查點切換後，例項就宕了。

恢復方法：

RMAN>  restore controlfile from '/home/oracle/rman/full_08tpot0t_1_1';
 
Starting restore at 13-FEB-19
using channel ORA_DISK_1
 
channel ORA_DISK_1: restoring control file
channel ORA_DISK_1: restore complete, elapsed time: 00:00:01
output file name=/oracle/app/oradata/orcl/control01.ctl
output file name=/oracle/app/oradata/orcl/control02.ctl
Finished restore at 13-FEB-19
 
RMAN> recover database;//對控制檔案進行歸檔+redo恢復
RMAN> alter database open resetlogs;
 
database opened

三、沒有 rman 備份的恢復

[oracle@redhat11g8 orcl]$ echo ''>control01.ctl
[oracle@redhat11g8 orcl]$ echo ''>control02.ctl
[oracle@redhat11g8 orcl]$ !sql
sqlplus / as sysdba
 
SQL*Plus: Release 11.2.0.4.0 Production on Wed Feb 13 08:59:38 2019
 
Copyright (c) 1982, 2013, Oracle.  All rights reserved.
 
 
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
 
SQL> alter system checkpoint;
alter system checkpoint
*
ERROR at line 1:
ORA-03113: end-of-file on communication channel
Process ID: 27123
Session ID: 72 Serial number: 3

恢復方法，若是還能 mount 的話倒簡單，

alter database backup controlfile to trace as '/tmp/ctl.txt';

即可，如果不能 mount 的話，只能麻煩點恢復：

透過引數檔案獲取資料庫名：

SQL> startup nomount;
ORACLE instance started.
 
Total System Global Area 2471931904 bytes
Fixed Size            2255752 bytes
Variable Size          620758136 bytes
Database Buffers     1845493760 bytes
Redo Buffers            3424256 bytes
SQL> create pfile='/tmp/orcl.ora' from spfile;
 
File created.
 
*.db_name='orcl'

查詢字符集：

SQL> select userenv('language') from dual;
 
USERENV('LANGUAGE')
----------------------------------------------------
AMERICAN_AMERICA.US7ASCII

獲取資料檔名和 redo 檔名：

[oracle@redhat11g8 orcl]$ ls -lh *.dbf
-rw-r-----. 1 oracle oinstall 254M Feb 13 08:54 jason01.dbf
-rw-r-----. 1 oracle oinstall 101M Feb 13 08:54 odc01.dbf
-rw-r-----. 1 oracle oinstall 1.3G Feb 13 08:54 sysaux01.dbf
-rw-r-----. 1 oracle oinstall 781M Feb 13 08:54 system01.dbf
-rw-r-----. 1 oracle oinstall 9.9G Feb 13 08:54 temp01.dbf
-rw-r-----. 1 oracle oinstall  11M Feb  3 06:50 temp02.dbf
-rw-r-----. 1 oracle oinstall 2.6G Feb 13 08:54 test.dbf
-rw-r-----. 1 oracle oinstall 1.9G Feb 13 08:54 undotbs01.dbf
-rw-r-----. 1 oracle oinstall  11G Feb 13 08:54 users01.dbf
 
[oracle@redhat11g8 orcl]$ ls -lh *.log
-rw-r-----. 1 oracle oinstall 51M Feb 13 08:54 redo01.log
-rw-r-----. 1 oracle oinstall 51M Feb 13 08:54 redo02.log
-rw-r-----. 1 oracle oinstall 51M Feb 13 08:59 redo03.log

編寫重建指令碼 ( 注意臨時檔案不要寫進重建指令碼里，不然會報如下錯誤 ) ：

ERROR at line 1:
ORA-01503: CREATE CONTROLFILE failed
ORA-01160: file is not a data file
ORA-01110: data file : '/oracle/app/oradata/orcl/temp01.dbf'

CREATE CONTROLFILE REUSE DATABASE "ORCL" RESETLOGS  ARCHIVELOG
    MAXLOGFILES 16
    MAXLOGMEMBERS 3
    MAXDATAFILES 100
    MAXINSTANCES 8
    MAXLOGHISTORY 292
LOGFILE
  GROUP 1 '/oracle/app/oradata/orcl/redo01.log'  SIZE 50M BLOCKSIZE 512,
  GROUP 2 '/oracle/app/oradata/orcl/redo02.log'  SIZE 50M BLOCKSIZE 512,
  GROUP 3 '/oracle/app/oradata/orcl/redo03.log'  SIZE 50M BLOCKSIZE 512
-- STANDBY LOGFILE
DATAFILE
  '/oracle/app/oradata/orcl/jason01.dbf',
  '/oracle/app/oradata/orcl/odc01.dbf',
  '/oracle/app/oradata/orcl/sysaux01.dbf',
  '/oracle/app/oradata/orcl/system01.dbf',
  '/oracle/app/oradata/orcl/test.dbf',
  '/oracle/app/oradata/orcl/undotbs01.dbf',
  '/oracle/app/oradata/orcl/users01.dbf'
CHARACTER SET US7ASCII
;
 
SQL> alter database open resetlogs;

Database altered.

四、注意事項

1 、除了 2.1 這種透過 cp 另一個控制檔案恢復的情景，其他情景都需要在恢復完後做一個 RMAN 全備份，因為 resetlogs 開啟後，之前的備份片都會失效。

2 、控制檔案最好能做冗餘，就算壞了一個，還可以用另一個恢復。