[20160405]bbed修改文件头.txt
[20160405]bbed修改文件头.txt
--以前做过一次,重复测试:
http://blog.itpub.net/267265/viewspace-746222/
如果数据库数据文件损坏,并且archivelog损坏,这样无法完全恢复,如果仅仅某个数据文件的scn与其他文件不同步,导致该数据文件无法mount.
正常可以像odu之类的工具恢复.但是在实际上如果修改数据文件的scn保持同步,这样数据库可以正常打开,选择常规的方法imp/exp以及expdp/impdp
方式恢复,这样虽然丢失一部分数据,至少一定程度减少损失.
--以前测试有点乱.
1.环境:
--冷备份数据库:
$ cp tea01.dbf tea01.dbf_ORG
SYS@book> @ &r/ver1
PORT_STRING VERSION BANNER
------------------------------ -------------- --------------------------------------------------------------------------------
x86_64/Linux 2.4.xx 11.2.0.4.0 Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
RMAN> report schema;
using target database control file instead of recovery catalog
Report of database schema for database with db_unique_name BOOK
List of Permanent Datafiles
===========================
File Size(MB) Tablespace RB segs Datafile Name
---- -------- -------------------- ------- ------------------------
1 770 SYSTEM *** /mnt/ramdisk/book/system01.dbf
2 1580 SYSAUX *** /mnt/ramdisk/book/sysaux01.dbf
3 1435 UNDOTBS1 *** /mnt/ramdisk/book/undotbs01.dbf
4 500 USERS *** /mnt/ramdisk/book/users01.dbf
5 346 EXAMPLE *** /mnt/ramdisk/book/example01.dbf
6 100 SUGAR *** /mnt/ramdisk/book/sugar01.dbf
7 1 TEA *** /mnt/ramdisk/book/tea01.dbf
List of Temporary Files
=======================
File Size(MB) Tablespace Maxsize(MB) Tempfile Name
---- -------- -------------------- ----------- --------------------
1 400 TEMP 32767 /mnt/ramdisk/book/temp01.dbf
SYS@book> select * from scott.empx where rownum<=1;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
---------- ---------- --------- ---------- ------------------- ---------- ---------- ----------
7369 YYYY CLERK 7902 1980-12-17 00:00:00 800 20
SYS@book> update scott.empx set ename='ZZZZ' where EMPNO=7369;
1 row updated.
SYS@book> commit ;
Commit complete.
alter system archive log current ;
/
/
/
2.假设现在数据库破坏,tea文件仅仅存在旧的备份,看看是否online看看.
SYS@book> shutdown immediate ;
Database closed.
Database dismounted.
ORACLE instance shut down.
$ cp tea01.dbf tea01.dbf_0405
$ mv tea01.dbf_ORG tea01.dbf
--模拟归档丢失.
$ cd /u01/app/oracle/archivelog/
$ mv book book.xxx
$ mkdir book
3.测试:
SYS@book> startup
ORACLE instance started.
Total System Global Area 634732544 bytes
Fixed Size 2255792 bytes
Variable Size 197133392 bytes
Database Buffers 427819008 bytes
Redo Buffers 7524352 bytes
Database mounted.
ORA-01113: file 7 needs media recovery
ORA-01110: data file 7: '/mnt/ramdisk/book/tea01.dbf'
--都是归档,无法恢复.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header;
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ------- ---------------- --- -------------------------------- ----------------
1 13227502431 2016-04-05 11:33:18 7 13227286650 ONLINE 1008 NO /mnt/ramdisk/book/system01.dbf SYSTEM
2 13227502431 2016-04-05 11:33:18 1834 13227286650 ONLINE 1004 NO /mnt/ramdisk/book/sysaux01.dbf SYSAUX
3 13227502431 2016-04-05 11:33:18 923328 13227286650 ONLINE 924 NO /mnt/ramdisk/book/undotbs01.dbf UNDOTBS1
4 13227502431 2016-04-05 11:33:18 16143 13227286650 ONLINE 1008 NO /mnt/ramdisk/book/users01.dbf USERS
5 13227502431 2016-04-05 11:33:18 952916 13227286650 ONLINE 921 NO /mnt/ramdisk/book/example01.dbf EXAMPLE
6 13227502431 2016-04-05 11:33:18 1314508 13227286650 ONLINE 937 NO /mnt/ramdisk/book/sugar01.dbf SUGAR
7 13227500866 2016-03-31 08:53:17 13227207527 13227286650 ONLINE 25 NO /mnt/ramdisk/book/tea01.dbf TEA
7 rows selected.
SYS@book> @ &r/10to16 13227502431
10 to 16 HEX REVERSE16
-------------- -----------------------------------
00003146bab5f 0x5fab6b14-03000000
SYS@book> @ &r/10to16 13227500866
10 to 16 HEX REVERSE16
-------------- -----------------------------------
00003146ba542 0x42a56b14-03000000
BBED> p kcvfh.kcvfhckp.kcvcpscn.kscnbas dba 7,1
ub4 kscnbas @484 0x146ba542
BBED> p kcvfh.kcvfhckp.kcvcpscn.kscnbas dba 1,1
ub4 kscnbas @484 0x146bab5f
BBED> assign dba 7,1 kcvfh.kcvfhckp.kcvcpscn.kscnbas = dba 1,1 kcvfh.kcvfhckp.kcvcpscn.kscnbas;
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
ub4 kscnbas @484 0x146bab5f
BBED> sum apply dba 7.1
BBED-00205: illegal or out of range DBA (File 0, Block 7)
BBED> sum apply dba 7,1
Check value for File 7, Block 1:
current = 0x0b12, required = 0x0b12
BBED> verify dba 7,1
DBVERIFY - Verification starting
FILE = /mnt/ramdisk/book/tea01.dbf
BLOCK = 1
DBVERIFY - Verification complete
Total Blocks Examined : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing (Index): 0
Total Blocks Empty : 0
Total Blocks Marked Corrupt : 0
Total Blocks Influx : 0
Message 531 not found; product=RDBMS; facility=BBED
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header;
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ------- ---------------- --- -------------------------------- ---------------
1 13227502431 2016-04-05 11:33:18 7 13227286650 ONLINE 1008 NO /mnt/ramdisk/book/system01.dbf SYSTEM
2 13227502431 2016-04-05 11:33:18 1834 13227286650 ONLINE 1004 NO /mnt/ramdisk/book/sysaux01.dbf SYSAUX
3 13227502431 2016-04-05 11:33:18 923328 13227286650 ONLINE 924 NO /mnt/ramdisk/book/undotbs01.dbf UNDOTBS1
4 13227502431 2016-04-05 11:33:18 16143 13227286650 ONLINE 1008 NO /mnt/ramdisk/book/users01.dbf USERS
5 13227502431 2016-04-05 11:33:18 952916 13227286650 ONLINE 921 NO /mnt/ramdisk/book/example01.dbf EXAMPLE
6 13227502431 2016-04-05 11:33:18 1314508 13227286650 ONLINE 937 NO /mnt/ramdisk/book/sugar01.dbf SUGAR
7 13227502431 2016-03-31 08:53:17 13227207527 13227286650 ONLINE 25 NO /mnt/ramdisk/book/tea01.dbf TEA
7 rows selected.
SYS@book> alter database open ;
alter database open
*
ERROR at line 1:
ORA-01113: file 7 needs media recovery
ORA-01110: data file 7: '/mnt/ramdisk/book/tea01.dbf'
SYS@book> recover datafile 7 ;
Media recovery complete.
SYS@book> alter database open ;
Database altered.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header;
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ------- ---------------- --- ------------------------------- ---------------
1 13227502434 2016-04-05 11:43:01 7 13227286650 ONLINE 1009 YES /mnt/ramdisk/book/system01.dbf SYSTEM
2 13227502434 2016-04-05 11:43:01 1834 13227286650 ONLINE 1005 YES /mnt/ramdisk/book/sysaux01.dbf SYSAUX
3 13227502434 2016-04-05 11:43:01 923328 13227286650 ONLINE 925 YES /mnt/ramdisk/book/undotbs01.dbf UNDOTBS1
4 13227502434 2016-04-05 11:43:01 16143 13227286650 ONLINE 1009 YES /mnt/ramdisk/book/users01.dbf USERS
5 13227502434 2016-04-05 11:43:01 952916 13227286650 ONLINE 922 YES /mnt/ramdisk/book/example01.dbf EXAMPLE
6 13227502434 2016-04-05 11:43:01 1314508 13227286650 ONLINE 938 YES /mnt/ramdisk/book/sugar01.dbf SUGAR
7 13227502434 2016-04-05 11:43:01 13227207527 13227286650 ONLINE 32 YES /mnt/ramdisk/book/tea01.dbf TEA
7 rows selected.
--自动修复CHECKPOINT_COUNT记数.视乎11.2.0.4不再需要修改CHECKPOINT_COUNT.
SYS@book> select * from scott.empx where rownum<=1;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
------------ ---------- --------- ------------ ------------------- ------------ ------------ ------------
7369 YYYY CLERK 7902 1980-12-17 00:00:00 800 20
--不过修改都丢失了.还原:
$ mv tea01.dbf_0405 tea01.dbf
$ cd /u01/app/oracle/archivelog/
$ mv book book.test
$ mv book.xxx/ book
SYS@book> startup mount
ORACLE instance started.
Total System Global Area 634732544 bytes
Fixed Size 2255792 bytes
Variable Size 197133392 bytes
Database Buffers 427819008 bytes
Redo Buffers 7524352 bytes
Database mounted.
SYS@book> alter database open ;
alter database open
*
ERROR at line 1:
ORA-01113: file 7 needs media recovery
ORA-01110: data file 7: '/mnt/ramdisk/book/tea01.dbf'
SYS@book> recover datafile 7 ;
Media recovery complete.
SYS@book> alter database open ;
Database altered.
SYS@book> select * from scott.empx where rownum<=1;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
---------- ---------- --------- ---------- ------------------- ---------- ---------- ----------
7369 ZZZZ CLERK 7902 1980-12-17 00:00:00 800 20
--OK,已经还原了.
--CHECKPOINT_COUNT的位置:
BBED> p kcvfh.kcvfhcpc dba 7,1
ub4 kcvfhcpc @140 0x00000023
BBED> p kcvfh.kcvfhcpc dba 1,1
ub4 kcvfhcpc @140 0x000003f3
SYS@book> @ &r/16to10 3f3
16 to 10 DEC
------------
1011
SYS@book> @ &r/16to10 23
16 to 10 DEC
------------
35
--实际上这样的测试存在许多问题,比如drop表,create表,这样在系统表空间存在定义,而数据文件已经丢失了.