[20170309]dg环境下在线日志损坏13.txt
http://blog.itpub.net/267265/viewspace-2134665/
http://blog.itpub.net/267265/viewspace-2134481/
--//按照如下链接,拷贝备用日志到主库,修改文件头偏移0x230 日志组号.以及hws,eot对应位置,欺骗oracle是正常的日志文件.
http://blog.itpub.net/267265/viewspace-2134816/
--//看了一些文档,在论坛问一下,感觉修改组号以及eot=1就ok了,hws不用修改.到现在还不理解hws表示什么??
--//我在论坛问hws等表示什么?链接
http://www.itpub.net/thread-2084723-1-1.html
eot : End Of Thread: indicates if this is the last log
hws = Hdr Write Seq#
dis : DISabled - true if thread disabled at end of this log
--//再次感谢刘工的解答. eot=1明显表示当前日志,而备用日志这里是0,感觉修改这里才是关键.
--//测试看看这样的情况:
1.环境:
--//首先还原环境,我包括异常关机的冷备份,拷贝回来,删除主库的在线日志以及备用日志.
SYS@book> @ &r/ver
BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
SYS@book> @ &r/logfile
GROUP# STATUS TYPE MEMBER IS_ GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE# NEXT_TIME
------ ------ ------- ------------------------------- --- ------ ------- --------- ----------- --------- ------- --- ---------- ------------- ------------------- ------------ -------------------
1 ONLINE /mnt/ramdisk/book/redo01.log NO 1 1 695 52428800 512 1 NO CURRENT 13276910949 2017-02-28 14:40:12 2.814750E+14
2 ONLINE /mnt/ramdisk/book/redo02.log NO 2 1 693 52428800 512 1 YES INACTIVE 13276889179 2017-02-27 08:59:01 13276910486 2017-02-28 14:40:06
3 ONLINE /mnt/ramdisk/book/redo03.log NO 3 1 694 52428800 512 1 YES ACTIVE 13276910486 2017-02-28 14:40:06 13276910949 2017-02-28 14:40:12
4 STANDBY /mnt/ramdisk/book/redostb01.log NO
5 STANDBY /mnt/ramdisk/book/redostb02.log NO
6 STANDBY /mnt/ramdisk/book/redostb03.log NO
7 STANDBY /mnt/ramdisk/book/redostb04.log NO
7 rows selected.
--//一些操作参考,不再重复:
http://blog.itpub.net/267265/viewspace-2134816/
2.拷贝备用日志到主机:
$ scp /mnt/ramdisk/book/redostb01.log oracle@192.168.100.78:/mnt/ramdisk/book/redo01.log
oracle@192.168.100.78's password:
redostb01.log 100% 50MB 25.0MB/s 00:02
--//注意这样因为redo的文件头不一样,oracle不会认为那个文件group#1的.
3.修改备用日志文件.
$ bvi80 -s 512 -b 512 /mnt/ramdisk/book/redo01.log
00000200 01 22 00 00 01 00 00 00 B7 02 00 00 00 80 9C B5 ................
00000210 00 00 00 00 00 04 20 0B 6E 21 B7 4F 42 4F 4F 4B ...... .n!.OBOOK
00000220 00 00 00 00 2D 8D 00 00 00 90 01 00 00 02 00 00 ....-...........
00000230 04 00 02 00 6E D8 B7 4F 00 00 00 00 00 00 00 00 ....n..O........
~~
00000240 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000250 00 00 00 00 00 00 00 00 00 00 00 00 54 68 72 65 ............Thre
00000260 61 64 20 30 30 30 31 2C 20 53 65 71 23 20 30 30 ad 0001, Seq# 00
00000270 30 30 30 30 30 36 39 35 2C 20 53 43 4E 20 30 78 00000695, SCN 0x
00000280 30 30 30 33 31 37 35 64 39 35 36 35 2D 30 78 66 0003175d9565-0xf
00000290 66 66 66 66 66 66 66 66 66 66 66 00 FF FF FF FF fffffffffff.....
000002A0 B0 1E 71 35 06 20 0E 00 00 00 00 00 02 00 00 00 ..q5. ..........
000002B0 01 00 00 00 65 95 5D 17 03 00 00 00 4C BB DB 37 ....e.].....L..7
000002C0 FF FF FF FF FF FF 00 00 00 00 00 00 00 00 00 02 ................
~~
000002D0 06 20 0E 00 00 00 00 00 B0 1E 71 35 65 95 5D 17 . ........q5e.].
000002E0 03 00 00 00 4C BB DB 37 00 00 00 00 00 20 82 00 ....L..7..... ..
000002F0 00 00 00 00 00 00 00 00 00 00 00 00 02 00 00 00 ................
00000300 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000310 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 ................
00000320 00 00 00 00 7A C9 21 31 00 00 00 00 00 00 00 00 ....z.!1........
00000330 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000340 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000350 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000360 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000370 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000380 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000390 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000003A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000003B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000003C0 12 E9 26 F7 7B 40 C0 80 DC 71 6E 8A 26 4C 32 9F ..&.{@...qn.&L2.
000003D0 27 F7 6C 1F 74 8A 40 20 48 9C 47 0B 46 31 76 E0 '.l.t.@ H.G.F1v.
000003E0 05 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000003F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000400 }
--//修改0x230处 0x04=>0x01. 将group#=1
--//修改0x2CA处 0x00=>0x01. 将eot=1.
--//9CB5 0400 0100 0000 0100 重新做异或操作
$ xor.sh a.txt
9CB5
0400
0100
0000
0100
xor result: 98B5
--//修改0x14,0x15 9CB5=>98B5
--//做异或参考链接:http://blog.itpub.net/267265/viewspace-2134945/
SYS@book> alter system dump logfile '/mnt/ramdisk/book/redo01.log' validate;
System altered.
DUMP OF REDO FROM FILE '/mnt/ramdisk/book/redo01.log'
Opcodes *.*
RBAs: 0x000000.00000000.0000 thru 0xffffffff.ffffffff.ffff
SCNs: scn: 0x0000.00000000 thru scn: 0xffff.ffffffff
Times: creation thru eternity
VALIDATE ONLY
FILE HEADER:
Compatibility Vsn = 186647552=0xb200400
Db ID=1337401710=0x4fb7216e, Db Name='BOOK'
Activation ID=1337448558=0x4fb7d86e
Control Seq=36141=0x8d2d, File size=102400=0x19000
File Number=1, Blksiz=512, File Type=2 LOG
descrip:"Thread 0001, Seq# 0000000695, SCN 0x0003175d9565-0xffffffffffff"
thread: 1 nab: 0xffffffff seq: 0x000002b7 hws: 0x2 eot: 1 dis: 0
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
resetlogs count: 0x35711eb0 scn: 0x0000.000e2006 (925702)
prev resetlogs count: 0x3121c97a scn: 0x0000.00000001 (1)
Low scn: 0x0003.175d9565 (13276910949) 02/28/2017 14:40:12
Next scn: 0xffff.ffffffff 01/01/1988 00:00:00
Enabled scn: 0x0000.000e2006 (925702) 11/24/2015 09:11:12
Thread closed scn: 0x0003.175d9565 (13276910949) 02/28/2017 14:40:12
Disk cksum: 0xb598 Calc cksum: 0xb598
Terminal recovery stop scn: 0x0000.00000000
Terminal recovery 01/01/1988 00:00:00
Most recent redo scn: 0x0000.00000000
Largest LWN: 0 blocks
End-of-redo stream : No
Maximize performance mode
Miscellaneous flags: 0x822000
Thread internal enable indicator: thr: 0, seq: 0 scn: 0x0000.00000000
Zero blocks: 0
Format ID is 2
redo log key is 12e926f77b40c080dc716e8a264c329f
redo log key flag is 5
Enabled redo threads: 1
END OF REDO DUMP
--//注意看~部分.
4.测试恢复:
SYS@book> recover database ;
ORA-00279: change 13276910487 generated at 02/28/2017 14:40:06 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_694_896605872.dbf
ORA-00280: change 13276910487 for thread 1 is in sequence #694
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
auto
ORA-00283: recovery session canceled due to errors
ORA-00338: log 1 of thread 1 is more recent than control file
ORA-00312: online log 1 thread 1: '/mnt/ramdisk/book/redo01.log'
ORA-01112: media recovery not started
SYS@book> recover database until cancel;
ORA-00279: change 13276910949 generated at 02/28/2017 14:40:12 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_695_896605872.dbf
ORA-00280: change 13276910949 for thread 1 is in sequence #695
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
/mnt/ramdisk/book/redo01.log
Log applied.
Media recovery complete.
--//最终确定仅仅修改日志组号以及eot标识为1.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header where file#=1;
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ---------- ---------------- --- ------------------------------ ---------------
1 13276911100 2017-02-28 14:42:35 7 925702 ONLINE 839 NO /mnt/ramdisk/book/system01.dbf SYSTEM
--//scn = 13276911100.
--//剩下的重复链接http://blog.itpub.net/267265/viewspace-2134816/操作.
--//确认这个文件记录的是seq#=694的日志文件.
$ scp /mnt/ramdisk/book/redostb02.log oracle@192.168.100.78:/mnt/ramdisk/book/redo03.log
oracle@192.168.100.78's password:
redostb02.log 100% 50MB 50.0MB/s 00:01
$ bvi80 -b 512 -s 512 /mnt/ramdisk/book/redo03.log
--//仅仅需要修改0x230处 0x0500 => 0x0300,重新计算检查和.
2B19
0500
0300
----
2D19
--//这个过程略.
SYS@book> alter database clear logfile group 2 ;
Database altered.
alter database clear logfile group 4 ;
alter database clear logfile group 5 ;
alter database clear logfile group 6 ;
alter database clear logfile group 7 ;
5.打开看看:
SYS@book> alter database open ;
alter database open
*
ERROR at line 1:
ORA-01589: must use RESETLOGS or NORESETLOGS option for database open
SYS@book> alter database open noresetlogs;
Database altered.
--//还第一次这样打这个命令使用noresetlogs打开.
--//ok,可以确定日志组号以及eot标识就ok了.
SYS@bookdg> @ &r/dg/dg
PROCESS PID STATUS CLIENT_P GROUP# THREAD# SEQUENCE# BLOCK# BLOCKS DELAY_MINS
--------- ------- ------------ -------- ------ ------- ---------- ---------- ---------- ----------
RFS 25707 IDLE UNKNOWN N/A 0 0 0 0 0
RFS 25709 IDLE LGWR 3 1 697 19 1 0
ARCH 25658 CLOSING ARCH 4 1 695 1 154 0
MRP0 25701 APPLYING_LOG N/A N/A 1 697 19 102400 0
--//日志传输与应用没有问题.
