UNDO段頭塊損壞測試與修復,本次案例通過BBED工具模擬UNDO段頭壞塊，並在沒有備份情況下啓動數據庫；
1 查看UNDO段頭塊位置
select header_file, header_block
from dba_segments
where segment_name like '_SYSSMU%'
order by 2;
2 通過BBED工具，破壞UNDO某一段的段頭塊(file=3 block=280)
破壞的方式是直接將其他的數據塊覆蓋段頭塊
[Oracle11@primary ~]$ bbed parfile=bbed.par
Password:
BBED: Release 2.0.0.0.0 - Limited Production on Sat Jul 30 18:00:26 2016
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
************* !!! For Oracle Internal Use only !!! ***************
BBED> copy dba 1,1 to dba 3,280
BBED> sum apply;
Check value for File 3, Block 280:
current = 0x599e, required = 0x599e
BBED> verify
DBVERIFY - Verification starting
FILE = /u02/app/oracle/oradata/orcl11/undotbs01.dbf
BLOCK = 280
Block 280 is corrupt
Corrupt block relative dba: 0x00400118 (file 0, block 280)
Bad header found during verification
Data in bad block:
type: 11 format: 2 rdba: 0x00400001
last change scn: 0x0000.00000000 seq: 0x1 flg: 0x04
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0x00000b01
check value in block header: 0xc8c7
computed block checksum: 0x0
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 : 1
Total Blocks Influx : 0
Message 531 not found; product=RDBMS; facility=BBED
---通過BBED和DBV檢查結果都是file3,block 280損壞
[oracle11@primary orcl11]$ dbv file=undotbs01.dbf
DBVERIFY: Release 11.2.0.4.0 - Production on Sat Jul 30 18:01:38 2016
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
DBVERIFY - Verification starting : FILE = /u02/app/oracle/oradata/orcl11/undotbs01.dbf
Page 280 is marked corrupt
Corrupt block relative dba: 0x00c00118 (file 3, block 280)
Bad header found during dbv:
Data in bad block:
type: 11 format: 2 rdba: 0x00400001
last change scn: 0x0000.00000000 seq: 0x1 flg: 0x04
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0x00000b01
check value in block header: 0xc8c7
computed block checksum: 0x0
DBVERIFY - Verification complete
Total Pages Examined : 392
Total Pages Processed (Data) : 0
Total Pages Failing (Data) : 0
Total Pages Processed (Index): 0
Total Pages Failing (Index): 0
Total Pages Processed (Other): 45
Total Pages Processed (Seg) : 23
Total Pages Failing (Seg) : 0
Total Pages Empty : 346
Total Pages Marked Corrupt : 1
Total Pages Influx : 0
Total Pages Encrypted : 0
Highest block SCN : 1283208 (0.1283208)
---模擬異常斷電
SQL> shutdown abort
ORACLE instance shut down.
---啓動數據庫，報錯ORA-01578
SQL> startup
ORACLE instance started.
Total System Global Area 784998400 bytes
Fixed Size 2257352 bytes
Variable Size 515903032 bytes
Database Buffers 264241152 bytes
Redo Buffers 2596864 bytes
Database mounted.
ORA-01092: ORACLE instance terminated. Disconnection forced
ORA-01578: ORACLE data block corrupted (file # 3, block # 280)
ORA-01110: data file 3: '/u02/app/oracle/oradata/orcl11/undotbs01.dbf'
Process ID: 8265
Session ID: 1 Serial number: 5
通常UNDO損壞，在沒有備份的情況下，可以通過以下方式啓動數據庫
#*.undo_tablespace='UNDOTBS1' ----註釋原UNDO表空間
#*.undo_management=AUTO ----UNDO管理方式改爲手動
*.undo_management='MANUAL'
*.undo_tablespace='SYSTEM' ---將UNDO表空間改成SYSTEM
*._corrupted_rollback_segments=損壞的回滾段 ---屏蔽損壞的UNDO段
創建新的回滾段:
create undo tablespace UNDOTBS2 datafile '/u02/app/oracle/oradata/orcl11/undotbs02.dbf' size 1M autoextend on;
刪除舊的回滾段:
drop tablespace UNDOTBS1 including contents and datafiles;
*.undo_tablespace='UNDOTBS2'
*.undo_management=AUTO
但是在mount狀態下無法查詢(創建或刪除)回滾段
SQL> select * from v$rollname;
select * from v$rollname
*
ERROR at line 1:
ORA-01219: database not open: queries allowed on fixed tables/views only
無法創建新的UNDO表空間
SQL> create undo tablespace UNDOTBS2 datafile '/u02/app/oracle/oradata/orcl11/undotbs02.dbf' size 1M autoextend on;
create undo tablespace UNDOTBS2 datafile '/u02/app/oracle/oradata/orcl11/undotbs02.dbf' size 1M autoextend on
*
ERROR at line 1:
ORA-01109: database not open
無法刪除舊的UNDO表空間
SQL> drop tablespace UNDOTBS1 including contents and datafiles;
drop tablespace UNDOTBS1 including contents and datafiles
*
ERROR at line 1:
ORA-01109: database not open
在數據庫不能OPEN情況下，有兩種方式可以查詢數據庫部分信息；
1：strings命令可以查詢所有的UNDO回滾段名，包括已經刪除的回滾段；
[oracle11@primary orcl11]$ strings system01.dbf | grep _SYSSMU | cut -d $ -f 1 | sort -u > listSMU
[oracle11@primary orcl11]$ vim listSMU
_SYSSMU20_3293637928$
_SYSSMU20_379396250$
_SYSSMU20_379396250$
_SYSSMU13_811223436$
........
2：BBED工具也可以查詢UNDO段名；
BBED> set file 1 block 225 -----Oracle 11g版本，undo$表信息一般位於1號文件第225個數據塊中
FILE# 1
BLOCK# 225
BBED> map
File: /u02/app/oracle/oradata/orcl11/system01.dbf (1)
Block: 225 Dba:0x004000e1
------------------------------------------------------------
KTB Data Block (Table/Cluster)
struct kcbh, 20 bytes @0
struct ktbbh, 48 bytes @20
struct kdbh, 14 bytes @68
struct kdbt[1], 4 bytes @82
sb2 kdbr[25] @86 -------含有25個UNDO段
ub1 freespace[6402] @136
ub1 rowdata[1650] @6538
ub4 tailchk @8188
BBED> p kdbr
sb2 kdbr[0] @86 8078
sb2 kdbr[1] @88 8011
sb2 kdbr[2] @90 7944
......
sb2 kdbr[22] @130 6603
sb2 kdbr[23] @132 6537
sb2 kdbr[24] @134 6470
BBED> x /rnc *kdbr[0] ----查看0號UNDO段名稱
col 1[6] @8151: SYSTEM
BBED> x /rnc *kdbr[1] ----查看1號UNDO段名稱
col 1[20] @8085: _SYSSMU1_4115952380$
如果UNDO段特別多，可以通過EXECL，自動生成多個x /rnc *kdbr[0]......*kdbr[n]命令，再將命令複製粘貼到BBED中，同時獲取多個UNDO段名；
x /rnc *kdbr[0]
x /rnc *kdbr[1]
x /rnc *kdbr[2]
x /rnc *kdbr[3]
......
x /rnc *kdbr[24]
如果不能判斷具體哪個回滾段出現問題，可以跳過所有的回滾段
*._corrupted_rollback_segments='_SYSSMU1_4115952380$','_SYSSMU2_3882698531$','_SYSSMU3_1780844141$','_SYSSMU4_1137450214$','_SYSSMU5_2972601029$','_SYSSMU6_2318781079$','_SYSSMU7_1865616030$','_SYSSMU8_4279519761$','_SYSSMU9_1551968587$','_SYSSMU10_2324134815$','_SYSSMU11_2069826877$','_SYSSMU12_2242918609$','_SYSSMU13_811223436$','_SYSSMU14_1093125402$','_SYSSMU15_2825991097$','_SYSSMU16_252471872$','_SYSSMU17_3347133763$','_SYSSMU18_1765883319$','_SYSSMU19_1005333767$','_SYSSMU20_3293637928$','_SYSSMU21_3641740596$','_SYSSMU22_3421614834$','_SYSSMU23_138031739$'
參數文件：
#*.undo_tablespace='UNDOTBS1'
#*.undo_management=AUTO
*.undo_tablespace='SYSTEM'
*.undo_management='MANUAL'
*._corrupted_rollback_segments='_SYSSMU1_4115952380$','_SYSSMU2_3882698531$','_SYSSMU3_1780844141$','_SYSSMU4_1137450214$','_SYSSMU5_2972601029$','_SYSSMU6_2318781079$','_SYSSMU7_1865616030$','_SYSSMU8_4279519761$','_SYSSMU9_1551968587$','_SYSSMU10_2324134815$','_SYSSMU11_2069826877$','_SYSSMU12_2242918609$','_SYSSMU13_811223436$','_SYSSMU14_1093125402$','_SYSSMU15_2825991097$','_SYSSMU16_252471872$','_SYSSMU17_3347133763$','_SYSSMU18_1765883319$','_SYSSMU19_1005333767$','_SYSSMU20_3293637928$','_SYSSMU21_3641740596$','_SYSSMU22_3421614834$','_SYSSMU23_138031739$'
SQL> shutdown immediate
SQL> startup
ORACLE instance started.
Total System Global Area 784998400 bytes
Fixed Size 2257352 bytes
Variable Size 515903032 bytes
Database Buffers 264241152 bytes
Redo Buffers 2596864 bytes
Database mounted.
Database opened.
創建新的UNDO表空間
create undo tablespace UNDOTBS2 datafile '/u02/app/oracle/oradata/orcl11/undotbs02.dbf' size 1M autoextend on;
刪除舊的UNDO表空間
drop tablespace UNDOTBS1 including contents and datafiles;
修改參數文件
*.undo_tablespace='UNDOTBS2'
*.undo_management=AUTO
#*.undo_tablespace='SYSTEM'
#*.undo_management='MANUAL'
#*._corrupted_rollback_segments='_SYSSMU1_4115952380$','_SYSSMU2_3882698531$','_SYSSMU3_1780844141$','_SYSSMU4_1137450214$','_SYSSMU5_2972601029$','_SYSSMU6_2318781079$','_SYSSMU7_1865616030$','_SYSSMU8_4279519761$','_SYSSMU9_1551968587$','_SYSSMU10_2324134815$','_SYSSMU11_2069826877$','_SYSSMU12_2242918609$','_SYSSMU13_811223436$','_SYSSMU14_1093125402$','_SYSSMU15_2825991097$','_SYSSMU16_252471872$','_SYSSMU17_3347133763$','_SYSSMU18_1765883319$','_SYSSMU19_1005333767$','_SYSSMU20_3293637928$','_SYSSMU21_3641740596$','_SYSSMU22_3421614834$','_SYSSMU23_138031739$'
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 784998400 bytes
Fixed Size 2257352 bytes
Variable Size 515903032 bytes
Database Buffers 264241152 bytes
Redo Buffers 2596864 bytes
Database mounted.
Database opened.
SQL> show parameter undo
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
undo_management string AUTO
undo_retention integer 900
undo_tablespace string UNDOTBS2
BBED修改數據塊是比較危險的操作，如果某個修改操作有誤，可以通過revert或undo命令回退BBED的修改操作；
例如：BBED回退3,280塊上所有修改
BBED> revert dba 3,280
All changes made to this block will be rolled back. Proceed? (Y/N) y
Reverted file '/u02/app/oracle/oradata/orcl11/undotbs01.dbf', block 280
BBED> sum apply;
Check value for File 3, Block 280:
current = 0x3f90, required = 0x3f90
UNDO非段頭(文件頭)塊損壞測試與修復
undo非段頭(文件頭)損壞，數據庫可以正常啓動，在沒有備份的情況下，可以通過alert報錯信息，找到並刪除受損的回滾段
SQL> insert into t values(1); -----插入一條數據，不提交
SQL> select usn,status,xacts from v$rollstat;
USN STATUS XACTS
---------- --------------- ----------
0 ONLINE 0
8 ONLINE 0
9 ONLINE 1 ----9號回滾段存在活動事物
10 ONLINE 0
11 ONLINE 0
12 ONLINE 0
24 ONLINE 0
25 ONLINE 0
26 ONLINE 0
27 ONLINE 0
28 ONLINE 0
11 rows selected.
---查看回滾段頭塊位置
SQL> SET LINE 100
SQL> col segment_name for a30
SQL> select segment_name,header_file,header_block from dba_segments where segment_name like '_SYSSMU%' order by 3;
SEGMENT_NAME HEADER_FILE HEADER_BLOCK
------------------------------ ----------- ------------
_SYSSMU8_4161384913$ 3 8
_SYSSMU9_1458183674$ 3 24
_SYSSMU10_2644453179$ 3 40
_SYSSMU11_4737420$ 3 56
_SYSSMU12_392022772$ 3 72
_SYSSMU24_4044825012$ 3 88
_SYSSMU25_2098992521$ 3 104
_SYSSMU26_2158116475$ 3 120
_SYSSMU27_4048022843$ 3 136
_SYSSMU28_1413754230$ 3 152
10 rows selected.
通過BBED工具，手動破壞9號回滾段非頭塊；
[oracle11@primary ~]$ bbed parfile=bbed.par
Password:
BBED: Release 2.0.0.0.0 - Limited Production on Sat Aug 13 22:35:38 2016
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
************* !!! For Oracle Internal Use only !!! ***************
BBED> copy dba 1,1 to dba 3,25
BBED> sum apply;
Check value for File 3, Block 25:
current = 0xae9a, required = 0xae9a
BBED> verify
DBVERIFY - Verification starting
FILE = /u02/app/oracle/oradata/orcl11/undotbs01.dbf
BLOCK = 25
Block 25 is corrupt
Corrupt block relative dba: 0x00400019 (file 3, block 25)
Bad header found during verification
Data in bad block:
type: 11 format: 2 rdba: 0x00400001
last change scn: 0x0000.00000000 seq: 0x1 flg: 0x04
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0x00000b01
check value in block header: 0xae9a
computed block checksum: 0x0
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 : 1
Total Blocks Influx : 0
Message 531 not found; product=RDBMS; facility=BBED
[oracle11@primary orcl11]$ dbv file=undotbs01.dbf
DBVERIFY: Release 11.2.0.4.0 - Production on Wed Aug 17 11:39:35 2016
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
DBVERIFY - Verification starting : FILE = /u02/app/oracle/oradata/orcl11/undotbs01.dbf
Page 25 is marked corrupt
Corrupt block relative dba: 0x00c00019 (file 3, block 25)
Bad header found during dbv:
Data in bad block:
type: 11 format: 2 rdba: 0x00400001
last change scn: 0x0000.00000000 seq: 0x1 flg: 0x04
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0x00000b01
check value in block header: 0xae9a
computed block checksum: 0x0
DBVERIFY - Verification complete
Total Pages Examined : 208
Total Pages Processed (Data) : 0
Total Pages Failing (Data) : 0
Total Pages Processed (Index): 0
Total Pages Failing (Index): 0
Total Pages Processed (Other): 88
Total Pages Processed (Seg) : 10
Total Pages Failing (Seg) : 0
Total Pages Empty : 119
Total Pages Marked Corrupt : 1
Total Pages Influx : 0
Total Pages Encrypted : 0
Highest block SCN : 1570655 (0.1570655)
SQL> shutdown abort
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 784998400 bytes
Fixed Size 2257352 bytes
Variable Size 515903032 bytes
Database Buffers 264241152 bytes
Redo Buffers 2596864 bytes
Database mounted.
Database opened.
數據庫可以正常啓動，後臺alert日誌也沒有報錯，通過dbv或者bbed工具檢查出壞塊後，可以手動刪除壞塊對應的undo段：
(1)：select * from dba_extents where file_id=xx and xxx between block_id and block_id+blocks-1;
(2)：DROP ROLLBACK SEGMENT rollback_segment;
或者直接新建UNDO表空間：
(1)：創建新的UNDO表空間
create undo tablespace UNDOTBS2 datafile '/u02/app/oracle/oradata/orcl11/undotbs02.dbf' size 1M autoextend on;
(2)：刪除舊的UNDO表空間
drop tablespace UNDOTBS1 including contents and datafiles;
UNDO文件頭塊損壞測試與修復
UNDO文件頭損壞，無法正常open數據庫；
SQL> shutdown abort
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 784998400 bytes
Fixed Size 2257352 bytes
Variable Size 515903032 bytes
Database Buffers 264241152 bytes
Redo Buffers 2596864 bytes
Database mounted.
ORA-01122: database file 3 failed verification check
ORA-01110: data file 3: '/u02/app/oracle/oradata/orcl11/undotbs01.dbf'
ORA-01210: data file header is media corrupt
在沒有備份的情況下，需要通過BBED工具進行修復損壞的文件頭；
修復的方式是通過複製其他數據文件頭，並手動修改文件頭中相關信息；
1、修改數據的DBA,rdba_kcbh
2、修改文件的大小，kccfhfsz
3、修改文件號，kccfhfno
4、修改文件創建時SCN，kcvfhcrs
5、修改文件創建時間，kcvfhcrt
6、修改表空間號，kcvfhtsn
7、修改相對文件號，kcvfhrfn
8、修改表空間的名稱， kcvfhtnm
9、修改表空間的長度，kcvfhtln
10、修改檢查點的SCN，kcvfhckp
11、修改檢查點的時間，kcvcptim
12、修改檢查點的計數器，kcvfhcpc
13、修改檢查點的控制文件備份的計數器， kcvfhccc
14、如果你修改是1號文件的1號塊，他的root rdba的地針是指向了bootstrap$
通過BBED修復UNDO文件頭壞塊過程比較複製，並且BBED工具並不對外公開，也不提供技術支持，使用過程中很容易出現問題，建議在正式環境儘量避免使用BBED工具；
可以通過下面網站查看具體修改過程；
http://blog.csdn.net/guoyjoe/article/details/31018075
BBED工具的安裝
Oracle 11g版本和以後的版本已經不提供bbed工具了，11g數據庫如果需要使用bbed工具，可以拷貝10g或之前版本數據庫上的三個文件:
[oracle11@primary ~]$ ll -rth bbed_install/
total 20K
-rw-r--r-- 1 root root 8.5K Sep 8 2012 bbedus.msb
-rw-r--r-- 1 root root 1.9K Sep 8 2012 sbbdpt.o
-rw-r--r-- 1 root root 1.2K Sep 8 2012 ssbbded.o
將文件拷貝到指定目錄
[oracle11@primary ~]$ cp /home/oracle11/bbed_install/bbedus.msb /u02/app/oracle/
product/11.2.0/rdbms/mesg/
[oracle11@primary ~]$ cp /home/oracle11/bbed_install/ssbbded.o /u02/app/oracle/product/11.2.0/rdbms/lib/
[oracle11@primary ~]$ cp /home/oracle11/bbed_install/sbbdpt.o /u02/app/oracle/product/11.2.0/rdbms/lib/
編譯
[oracle11@primary ~]$ make -f /u02/app/oracle/product/11.2.0/rdbms/lib/ins_rdbms
.mk BBED=$ORACLE_HOME/bin/bbed $ORACLE_HOME/bin/bbed
bbed默認密碼"blockedit"
[oracle11@primary ~]$ bbed
Password:
BBED: Release 2.0.0.0.0 - Limited Production on Sat Jul 30 14:22:17 2016
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
************* !!! For Oracle Internal Use only !!! ***************
BBED>
使用BBED工具之前需要創建filelist文件
SQL> set linesize 100
SQL> col name for a45
SQL> spool /home/oracle11/filelist.txt
SQL> select file#,name,bytes from v$datafile order by 1;
FILE# NAME BYTES
---------- --------------------------------------------- ----------
1 /u02/app/oracle/oradata/orcl11/system01.dbf 775946240
2 /u02/app/oracle/oradata/orcl11/sysaux01.dbf 545259520
3 /u02/app/oracle/oradata/orcl11/undotbs01.dbf 73400320
4 /u02/app/oracle/oradata/orcl11/users01.dbf 5242880
5 /u02/app/oracle/oradata/orcl11/chen01.dbf 1048576
SQL> spool off
[oracle11@primary ~]$ touch bbed.par
[oracle11@primary ~]$ vim bbed.par
blocksize=8192
listfile=/home/oracle11/filelist.txt
mode=edit
[oracle11@primary ~]$ bbed parfile=bbed.par
Password:
BBED: Release 2.0.0.0.0 - Limited Production on Sat Jul 30 14:36:34 2016
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
************* !!! For Oracle Internal Use only !!! ***************
BBED> show
FILE# 1
BLOCK# 1
OFFSET 0
DBA 0x00400001 (4194305 1,1)
FILENAME /u02/app/oracle/oradata/orcl11/system01.dbf
BIFILE bifile.bbd
LISTFILE /home/oracle11/filelist.txt
BLOCKSIZE 8192
MODE Edit
EDIT Unrecoverable
IBASE Dec
OBASE Dec
WIDTH 80
COUNT 512
LOGFILE log.bbd
SPOOL No