跳过丢失归档进行恢复

在我们恢复的时候，发现中间缺失归档，大部分dba认为从缺失的归档开始以后的归档都无法进行恢复。但是我们从非常规的方式，修改数据文件对应的信息是可以跳过该缺失的归档，并且利用后面的归档进行恢复的。 SYS@orcl11grecover datafile 6;ORA-00279: change

在我们恢复的时候，发现中间缺失归档，大部分dba认为从缺失的归档开始以后的归档都无法进行恢复。但是我们从非常规的方式，修改数据文件对应的信息是可以跳过该缺失的归档，并且利用后面的归档进行恢复的。

SYS@orcl11g>recover datafile 6;
ORA-00279: change 2054392 generated at 10/28/2014 23:20:14 needed for thread 1
ORA-00289: suggestion : /opt/oracle/flash_recovery_area/ORCL11G/archivelog/2014_10_28/o1_mf_1_150_b50rqvq8_.arc
ORA-00280: change 2054392 for thread 1 is in sequence #150

Specify log: {=suggested | filename | AUTO | CANCEL}

ORA-00326: log begins at change 2055246, need earlier change 2054392
ORA-00334: archived log: '/opt/oracle/flash_recovery_area/ORCL11G/archivelog/2014_10_28/o1_mf_1_150_b50rqvq8_.arc'

这里我们发现对应的归档文件已经丢失，无法进行恢复
这里我们通过bbed只需要修改两个地方即可跳过该归档，使用下一个归档进行恢复：

BBED> p kcvfhckp
struct kcvfhckp, 36 bytes                   @484    
   struct kcvcpscn, 8 bytes                 @484    
      ub4 kscnbas                           @484      0x001f58f8
      ub2 kscnwrp                           @488      0x0000
   ub4 kcvcptim                             @492      0x3363df2e
   ub2 kcvcpthr                             @496      0x0001
   union u, 12 bytes                        @500    
      struct kcvcprba, 12 bytes             @500    
         ub4 kcrbaseq                       @500      0x00000095
         ub4 kcrbabno                       @504      0x00000002
         ub2 kcrbabof                       @508      0x0010
   ub1 kcvcpetb[0]                          @512      0x02
   ub1 kcvcpetb[1]                          @513      0x00
   ub1 kcvcpetb[2]                          @514      0x00
   ub1 kcvcpetb[3]                          @515      0x00
   ub1 kcvcpetb[4]                          @516      0x00
   ub1 kcvcpetb[5]                          @517      0x00
   ub1 kcvcpetb[6]                          @518      0x00
   ub1 kcvcpetb[7]                          @519      0x00

BBED> modify /x 96 offset 500
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
File: /opt/oracle/oradata/orcl11g/zbdba01.dbf (6)
Block: 1                Offsets:  500 to 1011           Dba:0x01800001
------------------------------------------------------------------------
96000000 02000000 10000000 02000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 0d000d00 0d000100 00000000 00000000
00000000 02008001 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000



BBED> sum apply
Check value for File 6, Block 1:
current = 0x6ce1, required = 0x6ce1

BBED> verify
DBVERIFY - Verification starting
FILE = /opt/oracle/oradata/orcl11g/zbdba01.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


BBED> show all
        FILE#           6
        BLOCK#          1
        OFFSET          500
        DBA             0x01800001 (25165825 6,1)
        FILENAME        /opt/oracle/oradata/orcl11g/zbdba01.dbf
        BIFILE          bifile.bbd
        LISTFILE        filelist.txt
        BLOCKSIZE       8192
        MODE            Edit
        EDIT            Unrecoverable
        IBASE           Dec
        OBASE           Dec
        WIDTH           80
        COUNT           512
        LOGFILE         log.bbd
        SPOOL           No

BBED> modify /x 1f5c4e offset 484
File: /opt/oracle/oradata/orcl11g/zbdba01.dbf (6)
Block: 1                Offsets:  484 to  995           Dba:0x01800001
------------------------------------------------------------------------
1f5c4e00 00000000 2edf6333 01000000 96000000 02000000 10000000 02000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
0d000d00 0d000100 00000000 00000000 00000000 02008001 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000



BBED> sum apply
Check value for File 6, Block 1:
current = 0x6857, required = 0x6857

BBED> verify
DBVERIFY - Verification starting
FILE = /opt/oracle/oradata/orcl11g/zbdba01.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

再次进行恢复：

SYS@orcl11g>
SYS@orcl11g>
SYS@orcl11g>recover datafile 6;
Media recovery complete.
SYS@orcl11g>
SYS@orcl11g>
SYS@orcl11g>
SYS@orcl11g>
SYS@orcl11g>alter database datafile 6 online;

Database altered.

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