ASM磁盘头信息损坏和修复(kfed/dd)
转自：http://blog.csdn.net/zhengwei125/article/details/50836329
ASM磁盘头信息损坏和修复(kfed/dd)
KFED主要用来编辑和修复ASM metadata,可以在DiskGroup没有mount的情况下使用;因此在ASM无法启动、DiskGroup无法mount的时候可以尝试使用这个神器来修复。
kfed工具支持对于ASM信息的READ/WRITE/MERGE/NEW/ FORM/FIND/STRUCT等操作，11gR2之前需要手工编译.
一、编译kfed工具
1.编译
[oracle@node1 ~]$ cd $ORACLE_HOME/rdbms/lib
[oracle@node1 lib]$ make -f ins_rdbms.mk ikfed
2.配置环境变量
export PATH=$ORACLE_HOME/bin:$ORACLE_HOME/rdbms/lib:$PATH
3.查看帮助
[oracle@node1 ~]$ kfed -help
as/mlibASM Library [asmlib='lib']
aun/umAU number to examine or update [AUNUM=number]
aus/zAllocation Unit size in bytes [AUSZ=number]
blkn/umBlock number to examine or update [BLKNUM=number]
blks/zMetadata block size in bytes [BLKSZ=number]
ch/ksumUpdate checksum before each write [CHKSUM=YES/NO]
cn/tCount of AUs to process [CNT=number]
de/vASM device to examine or update [DEV=string]
dm/pallDon't suppress repeated lines when dumping corrupt blocks [DMPALL=YES/NO]
o/p KFED operation type [OP=READ/WRITE/MERGE/REPAIR/NEW/FORM/FIND/STRUCT]
p/rovnmName for provisioning purposes [PROVNM=string]
s/eekAU number to seek to [SEEK=number]
te/xtFile name for translated block text [TEXT=string]
ty/peASM metadata block type number [TYPE=number]
asm的每个磁盘上有存放有asm的元数据，元数据一般大小为4k。disk header一般在第0个au,第0个块上。
二、模拟损坏磁盘头信息
1. 备份磁盘头信息：
[root@axj-rac1 backup]#dd if=/dev/raw/raw5 of=/backup/raw5.bak bs=1M count=2
[root@axj-rac1 backup]#dd if=/dev/raw/raw6 of=/backup/raw6.bak bs=1M count=2
[root@axj-rac1 backup]#dd if=/dev/raw/raw7 of=/backup/raw7.bak bs=1M count=2
备份成txt格式
kfed read /dev/raw/raw6 text=/home/oracle/asmdisk_raw6.txt
2. 查看备份的磁盘头信息
[root@axj-rac1 oracle]# cat asmdisk_raw6.txt
kfbh.endian: 1 ; 0x000: 0x01
kfbh.hard: 130 ; 0x001: 0x82
kfbh.type: 1 ; 0x002: KFBTYP_DISKHEAD
kfbh.datfmt: 1 ; 0x003: 0x01
kfbh.block.blk: 0 ; 0x004: blk=0
kfbh.block.obj: 2147483649 ; 0x008: disk=1
kfbh.check: 3657275721 ; 0x00c: 0xd9fd9949
kfbh.fcn.base: 0 ; 0x010: 0x00000000
kfbh.fcn.wrap: 0 ; 0x014: 0x00000000
kfbh.spare1: 0 ; 0x018: 0x00000000
kfbh.spare2: 0 ; 0x01c: 0x00000000
kfdhdb.driver.provstr: ORCLDISK ; 0x000: length=8
kfdhdb.driver.reserved[0]: 0 ; 0x008: 0x00000000
kfdhdb.driver.reserved[1]: 0 ; 0x00c: 0x00000000
kfdhdb.driver.reserved[2]: 0 ; 0x010: 0x00000000
kfdhdb.driver.reserved[3]: 0 ; 0x014: 0x00000000
kfdhdb.driver.reserved[4]: 0 ; 0x018: 0x00000000
kfdhdb.driver.reserved[5]: 0 ; 0x01c: 0x00000000
kfdhdb.compat: 186646528 ; 0x020: 0x0b200000
kfdhdb.dsknum: 1 ; 0x024: 0x0001
kfdhdb.grptyp: 1 ; 0x026: KFDGTP_EXTERNAL --磁盘组冗余方式
kfdhdb.hdrsts: 3 ; 0x027: KFDHDR_MEMBER --磁盘组状态，3是可用状态
kfdhdb.dskname: DATADG01_0001 ; 0x028: length=13
kfdhdb.grpname: DATADG01 ; 0x048: length=8 --磁盘组名字
kfdhdb.fgname: DATADG01_0001 ; 0x068: length=13
kfdhdb.capname: ; 0x088: length=0
kfdhdb.crestmp.hi: 33026093 ; 0x0a8: HOUR=0xd DAYS=0x1 MNTH=0xc YEAR=0x7df
kfdhdb.crestmp.lo: 2356159488 ; 0x0ac: USEC=0x0 MSEC=0x9 SECS=0x7 MINS=0x23
kfdhdb.mntstmp.hi: 33032273 ; 0x0b0: HOUR=0x11 DAYS=0x2 MNTH=0x2 YEAR=0x7e0
kfdhdb.mntstmp.lo: 3209038848 ; 0x0b4: USEC=0x0 MSEC=0x183 SECS=0x34 MINS=0x2f
kfdhdb.secsize: 512 ; 0x0b8: 0x0200
kfdhdb.blksize: 4096 ; 0x0ba: 0x1000
kfdhdb.ausize: 1048576 ; 0x0bc: 0x00100000 --au的大小，单位是byte,大小是1M
kfdhdb.mfact: 113792 ; 0x0c0: 0x0001bc80
kfdhdb.dsksize: 4008 ; 0x0c4: 0x00000fa8 --该disk的大小，单位是au，默认au是1m，所以大小为4008M
kfdhdb.pmcnt: 2 ; 0x0c8: 0x00000002
kfdhdb.fstlocn: 1 ; 0x0cc: 0x00000001
kfdhdb.altlocn: 2 ; 0x0d0: 0x00000002
kfdhdb.f1b1locn: 0 ; 0x0d4: 0x00000000 --file directory所在的au位置
kfdhdb.redomirrors[0]: 0 ; 0x0d8: 0x0000
kfdhdb.redomirrors[1]: 0 ; 0x0da: 0x0000
kfdhdb.redomirrors[2]: 0 ; 0x0dc: 0x0000
kfdhdb.redomirrors[3]: 0 ; 0x0de: 0x0000
kfdhdb.dbcompat: 168820736 ; 0x0e0: 0x0a100000
kfdhdb.grpstmp.hi: 33024790 ; 0x0e4: HOUR=0x16 DAYS=0x18 MNTH=0xa YEAR=0x7df
kfdhdb.grpstmp.lo: 258378752 ; 0x0e8: USEC=0x0 MSEC=0x1a3 SECS=0x36 MINS=0x3
kfdhdb.vfstart: 0 ; 0x0ec: 0x00000000
kfdhdb.vfend: 0 ; 0x0f0: 0x00000000
kfdhdb.spfile: 0 ; 0x0f4: 0x00000000
kfdhdb.spfflg: 0 ; 0x0f8: 0x00000000
kfdhdb.ub4spare[0]: 0 ; 0x0fc: 0x00000000
kfdhdb.ub4spare[1]: 0 ; 0x100: 0x00000000
kfdhdb.ub4spare[2]: 0 ; 0x104: 0x00000000
kfdhdb.ub4spare[3]: 0 ; 0x108: 0x00000000
kfdhdb.ub4spare[4]: 0 ; 0x10c: 0x00000000
kfdhdb.ub4spare[5]: 0 ; 0x110: 0x00000000
kfdhdb.ub4spare[6]: 0 ; 0x114: 0x00000000
kfdhdb.ub4spare[7]: 0 ; 0x118: 0x00000000
kfdhdb.ub4spare[8]: 0 ; 0x11c: 0x00000000
kfdhdb.ub4spare[9]: 0 ; 0x120: 0x00000000
kfdhdb.ub4spare[10]: 0 ; 0x124: 0x00000000
kfdhdb.ub4spare[11]: 0 ; 0x128: 0x00000000
kfdhdb.ub4spare[12]: 0 ; 0x12c: 0x00000000
kfdhdb.ub4spare[13]: 0 ; 0x130: 0x00000000
kfdhdb.ub4spare[14]: 0 ; 0x134: 0x00000000
kfdhdb.ub4spare[15]: 0 ; 0x138: 0x00000000
kfdhdb.ub4spare[16]: 0 ; 0x13c: 0x00000000
kfdhdb.ub4spare[17]: 0 ; 0x140: 0x00000000
kfdhdb.ub4spare[18]: 0 ; 0x144: 0x00000000
kfdhdb.ub4spare[19]: 0 ; 0x148: 0x00000000
kfdhdb.ub4spare[20]: 0 ; 0x14c: 0x00000000
kfdhdb.ub4spare[21]: 0 ; 0x150: 0x00000000
kfdhdb.ub4spare[22]: 0 ; 0x154: 0x00000000
kfdhdb.ub4spare[23]: 0 ; 0x158: 0x00000000
kfdhdb.ub4spare[24]: 0 ; 0x15c: 0x00000000
kfdhdb.ub4spare[25]: 0 ; 0x160: 0x00000000
kfdhdb.ub4spare[26]: 0 ; 0x164: 0x00000000
kfdhdb.ub4spare[27]: 0 ; 0x168: 0x00000000
kfdhdb.ub4spare[28]: 0 ; 0x16c: 0x00000000
kfdhdb.ub4spare[29]: 0 ; 0x170: 0x00000000
kfdhdb.ub4spare[30]: 0 ; 0x174: 0x00000000
kfdhdb.ub4spare[31]: 0 ; 0x178: 0x00000000
kfdhdb.ub4spare[32]: 0 ; 0x17c: 0x00000000
kfdhdb.ub4spare[33]: 0 ; 0x180: 0x00000000
kfdhdb.ub4spare[34]: 0 ; 0x184: 0x00000000
kfdhdb.ub4spare[35]: 0 ; 0x188: 0x00000000
kfdhdb.ub4spare[36]: 0 ; 0x18c: 0x00000000
kfdhdb.ub4spare[37]: 0 ; 0x190: 0x00000000
kfdhdb.ub4spare[38]: 0 ; 0x194: 0x00000000
kfdhdb.ub4spare[39]: 0 ; 0x198: 0x00000000
kfdhdb.ub4spare[40]: 0 ; 0x19c: 0x00000000
kfdhdb.ub4spare[41]: 0 ; 0x1a0: 0x00000000
kfdhdb.ub4spare[42]: 0 ; 0x1a4: 0x00000000
kfdhdb.ub4spare[43]: 0 ; 0x1a8: 0x00000000
kfdhdb.ub4spare[44]: 0 ; 0x1ac: 0x00000000
kfdhdb.ub4spare[45]: 0 ; 0x1b0: 0x00000000
kfdhdb.ub4spare[46]: 0 ; 0x1b4: 0x00000000
kfdhdb.ub4spare[47]: 0 ; 0x1b8: 0x00000000
kfdhdb.ub4spare[48]: 0 ; 0x1bc: 0x00000000
kfdhdb.ub4spare[49]: 0 ; 0x1c0: 0x00000000
kfdhdb.ub4spare[50]: 0 ; 0x1c4: 0x00000000
kfdhdb.ub4spare[51]: 0 ; 0x1c8: 0x00000000
kfdhdb.ub4spare[52]: 0 ; 0x1cc: 0x00000000
kfdhdb.ub4spare[53]: 0 ; 0x1d0: 0x00000000
kfdhdb.acdb.aba.seq: 0 ; 0x1d4: 0x00000000
kfdhdb.acdb.aba.blk: 0 ; 0x1d8: 0x00000000
kfdhdb.acdb.ents: 0 ; 0x1dc: 0x0000
kfdhdb.acdb.ub2spare: 0 ; 0x1de: 0x0000
3.破坏磁盘头的元数据，这里我开始破坏了raw5,后来为达到效果又破坏了下面两个
[root@axj-rac1 backup]# dd if=/dev/zero of=/dev/raw/raw5 bs=4096 count=1
[root@axj-rac1 backup]# dd if=/dev/zero of=/dev/raw/raw6 bs=4096 count=1
[root@axj-rac1 backup]# dd if=/dev/zero of=/dev/raw/raw7 bs=4096 count=1
4.查看一下磁盘头的状态
col group_number format a30
col disk_number format a30
col name format a30
col header_status format a30
col path format a30
col group_number clear
col disk_number clear
set linesize 200 pagesize 2000
SQL> select group_number,disk_number,name,header_status,path from v$asm_disk;
GROUP_NUMBER DISK_NUMBER NAMEHEADER_STATU PATH
---------------------- ---------------------------
2 0 OCR_VOTE_0000MEMBER /dev/raw/raw1
1 1 DATADG01_0001MEMBER /dev/raw/raw6
2 1 OCR_VOTE_0001MEMBER /dev/raw/raw2
2 2 OCR_VOTE_0002MEMBER /dev/raw/raw3
1 0 DATADG01_0000MEMBER /dev/raw/raw5
1 2 DATADG01_0002MEMBER /dev/raw/raw7
上面是正常的状态
SQL> select group_number,disk_number,name,header_status,path from v$asm_disk;
GROUP_NUMBER DISK_NUMBER NAMEHEADER_STATUS PATH
------------ ---------------------------------------
2 0 OCR_VOTE_0000MEMBER /dev/raw/raw1
1 1 DATADG01_0001MEMBER /dev/raw/raw6
2 1 OCR_VOTE_0001MEMBER /dev/raw/raw2
2 2 OCR_VOTE_0002MEMBER /dev/raw/raw3
1 0 DATADG01_0000CANDIDATE /dev/raw/raw5
1 2 DATADG01_0002MEMBER /dev/raw/raw7
这里是破坏后的状态，raw状态为CANDIDATE
5.破坏后查看用kfed查看raw5的磁盘头的信息
[root@axj-rac1 oracle]# kfed read /dev/raw/raw5 aun=0 blkn=0
kfbh.endian: 0 ; 0x000: 0x00
kfbh.hard: 0 ; 0x001: 0x00
kfbh.type: 0 ; 0x002: KFBTYP_INVALID
kfbh.datfmt: 0 ; 0x003: 0x00
kfbh.block.blk: 0 ; 0x004: blk=0
kfbh.block.obj: 0 ; 0x008: file=0
kfbh.check: 0 ; 0x00c: 0x00000000
kfbh.fcn.base: 0 ; 0x010: 0x00000000
kfbh.fcn.wrap: 0 ; 0x014: 0x00000000
kfbh.spare1: 0 ; 0x018: 0x00000000
kfbh.spare2: 0 ; 0x01c: 0x00000000
7F5595918400 00000000 00000000 00000000 00000000 [................]
Repeat 255 times
KFED-00322: Invalid content encountered during block traversal: [kfbtTraverseBlock][Invalid OSM block type][][0]
可以看到已经报错了，跟上面的不一样了。
依次查看raw6和raw7的磁盘头信息
kfed read /backup/raw6.bak aun=1 blkn=254
kfed read /backup/raw7.bak aun=1 blkn=254
[root@axj-rac1 backup]# kfed read /backup/raw5.bak aun=1 blkn=254|grep kfbh.type
kfbh.type: 1 ; 0x002: KFBTYP_DISKHEAD
从10.2.0.5开始之后的版本header信息是有额外保护和备份的，那么备份在哪个位置
也是在disk的特定位置，这对au=1MB的dg，备份信息是在第510blkn的位置，我们可以看下位置510的信息：
[root@axj-rac1 backup]# kfed read /dev/raw/raw5 aun=0 blkn=510 | grep kfbh.type
kfbh.type: 1 ; 0x002: KFBTYP_DISKHEAD
可以看到510确实也是HEAD信息把它读出来看看
[root@axj-rac1 backup]# kfed read /dev/raw/raw5 blkn=510
kfbh.endian: 1 ; 0x000: 0x01
kfbh.hard: 130 ; 0x001: 0x82
kfbh.type: 1 ; 0x002: KFBTYP_DISKHEAD
kfbh.datfmt: 1 ; 0x003: 0x01
kfbh.block.blk: 254 ; 0x004: blk=254
kfbh.block.obj: 2147483648 ; 0x008: disk=0
kfbh.check: 323429756 ; 0x00c: 0x1347257c
kfbh.fcn.base: 16403 ; 0x010: 0x00004013
kfbh.fcn.wrap: 0 ; 0x014: 0x00000000
kfbh.spare1: 0 ; 0x018: 0x00000000
kfbh.spare2: 0 ; 0x01c: 0x00000000
kfdhdb.driver.provstr: ORCLDISK ; 0x000: length=8
kfdhdb.driver.reserved[0]: 0 ; 0x008: 0x00000000
kfdhdb.driver.reserved[1]: 0 ; 0x00c: 0x00000000
kfdhdb.driver.reserved[2]: 0 ; 0x010: 0x00000000
kfdhdb.driver.reserved[3]: 0 ; 0x014: 0x00000000
kfdhdb.driver.reserved[4]: 0 ; 0x018: 0x00000000
kfdhdb.driver.reserved[5]: 0 ; 0x01c: 0x00000000
kfdhdb.compat: 186646528 ; 0x020: 0x0b200000
kfdhdb.dsknum: 0 ; 0x024: 0x0000
kfdhdb.grptyp: 1 ; 0x026: KFDGTP_EXTERNAL
kfdhdb.hdrsts: 3 ; 0x027: KFDHDR_MEMBER
kfdhdb.dskname: DATADG01_0000 ; 0x028: length=13
kfdhdb.grpname: DATADG01 ; 0x048: length=8
kfdhdb.fgname: DATADG01_0000 ; 0x068: length=13
kfdhdb.capname: ; 0x088: length=0
kfdhdb.crestmp.hi: 33024790 ; 0x0a8: HOUR=0x16 DAYS=0x18 MNTH=0xa YEAR=0x7df
kfdhdb.crestmp.lo: 258502656 ; 0x0ac: USEC=0x0 MSEC=0x21c SECS=0x36 MINS=0x3
kfdhdb.mntstmp.hi: 33032273 ; 0x0b0: HOUR=0x11 DAYS=0x2 MNTH=0x2 YEAR=0x7e0
kfdhdb.mntstmp.lo: 3209038848 ; 0x0b4: USEC=0x0 MSEC=0x183 SECS=0x34 MINS=0x2f
kfdhdb.secsize: 512 ; 0x0b8: 0x0200
kfdhdb.blksize: 4096 ; 0x0ba: 0x1000
kfdhdb.ausize: 1048576 ; 0x0bc: 0x00100000
kfdhdb.mfact: 113792 ; 0x0c0: 0x0001bc80
kfdhdb.dsksize: 2008 ; 0x0c4: 0x000007d8
kfdhdb.pmcnt: 2 ; 0x0c8: 0x00000002
kfdhdb.fstlocn: 1 ; 0x0cc: 0x00000001
kfdhdb.altlocn: 2 ; 0x0d0: 0x00000002
kfdhdb.f1b1locn: 2 ; 0x0d4: 0x00000002
kfdhdb.redomirrors[0]: 0 ; 0x0d8: 0x0000
kfdhdb.redomirrors[1]: 65535 ; 0x0da: 0xffff
kfdhdb.redomirrors[2]: 65535 ; 0x0dc: 0xffff
kfdhdb.redomirrors[3]: 65535 ; 0x0de: 0xffff
kfdhdb.dbcompat: 168820736 ; 0x0e0: 0x0a100000
kfdhdb.grpstmp.hi: 33024790 ; 0x0e4: HOUR=0x16 DAYS=0x18 MNTH=0xa YEAR=0x7df
kfdhdb.grpstmp.lo: 258378752 ; 0x0e8: USEC=0x0 MSEC=0x1a3 SECS=0x36 MINS=0x3
kfdhdb.vfstart: 0 ; 0x0ec: 0x00000000
kfdhdb.vfend: 0 ; 0x0f0: 0x00000000
kfdhdb.spfile: 0 ; 0x0f4: 0x00000000
kfdhdb.spfflg: 0 ; 0x0f8: 0x00000000
kfdhdb.ub4spare[0]: 0 ; 0x0fc: 0x00000000
kfdhdb.ub4spare[1]: 0 ; 0x100: 0x00000000
kfdhdb.ub4spare[2]: 0 ; 0x104: 0x00000000
kfdhdb.ub4spare[3]: 0 ; 0x108: 0x00000000
kfdhdb.ub4spare[4]: 0 ; 0x10c: 0x00000000
kfdhdb.ub4spare[5]: 0 ; 0x110: 0x00000000
kfdhdb.ub4spare[6]: 0 ; 0x114: 0x00000000
kfdhdb.ub4spare[7]: 0 ; 0x118: 0x00000000
kfdhdb.ub4spare[8]: 0 ; 0x11c: 0x00000000
kfdhdb.ub4spare[9]: 0 ; 0x120: 0x00000000
kfdhdb.ub4spare[10]: 0 ; 0x124: 0x00000000
kfdhdb.ub4spare[11]: 0 ; 0x128: 0x00000000
kfdhdb.ub4spare[12]: 0 ; 0x12c: 0x00000000
kfdhdb.ub4spare[13]: 0 ; 0x130: 0x00000000
kfdhdb.ub4spare[14]: 0 ; 0x134: 0x00000000
kfdhdb.ub4spare[15]: 0 ; 0x138: 0x00000000
kfdhdb.ub4spare[16]: 0 ; 0x13c: 0x00000000
kfdhdb.ub4spare[17]: 0 ; 0x140: 0x00000000
kfdhdb.ub4spare[18]: 0 ; 0x144: 0x00000000
kfdhdb.ub4spare[19]: 0 ; 0x148: 0x00000000
kfdhdb.ub4spare[20]: 0 ; 0x14c: 0x00000000
kfdhdb.ub4spare[21]: 0 ; 0x150: 0x00000000
kfdhdb.ub4spare[22]: 0 ; 0x154: 0x00000000
kfdhdb.ub4spare[23]: 0 ; 0x158: 0x00000000
kfdhdb.ub4spare[24]: 0 ; 0x15c: 0x00000000
kfdhdb.ub4spare[25]: 0 ; 0x160: 0x00000000
kfdhdb.ub4spare[26]: 0 ; 0x164: 0x00000000
kfdhdb.ub4spare[27]: 0 ; 0x168: 0x00000000
kfdhdb.ub4spare[28]: 0 ; 0x16c: 0x00000000
kfdhdb.ub4spare[29]: 0 ; 0x170: 0x00000000
kfdhdb.ub4spare[30]: 0 ; 0x174: 0x00000000
kfdhdb.ub4spare[31]: 0 ; 0x178: 0x00000000
kfdhdb.ub4spare[32]: 0 ; 0x17c: 0x00000000
kfdhdb.ub4spare[33]: 0 ; 0x180: 0x00000000
kfdhdb.ub4spare[34]: 0 ; 0x184: 0x00000000
kfdhdb.ub4spare[35]: 0 ; 0x188: 0x00000000
kfdhdb.ub4spare[36]: 0 ; 0x18c: 0x00000000
kfdhdb.ub4spare[37]: 0 ; 0x190: 0x00000000
kfdhdb.ub4spare[38]: 0 ; 0x194: 0x00000000
kfdhdb.ub4spare[39]: 0 ; 0x198: 0x00000000
kfdhdb.ub4spare[40]: 0 ; 0x19c: 0x00000000
kfdhdb.ub4spare[41]: 0 ; 0x1a0: 0x00000000
kfdhdb.ub4spare[42]: 0 ; 0x1a4: 0x00000000
kfdhdb.ub4spare[43]: 0 ; 0x1a8: 0x00000000
kfdhdb.ub4spare[44]: 0 ; 0x1ac: 0x00000000
kfdhdb.ub4spare[45]: 0 ; 0x1b0: 0x00000000
kfdhdb.ub4spare[46]: 0 ; 0x1b4: 0x00000000
kfdhdb.ub4spare[47]: 0 ; 0x1b8: 0x00000000
kfdhdb.ub4spare[48]: 0 ; 0x1bc: 0x00000000
kfdhdb.ub4spare[49]: 0 ; 0x1c0: 0x00000000
kfdhdb.ub4spare[50]: 0 ; 0x1c4: 0x00000000
kfdhdb.ub4spare[51]: 0 ; 0x1c8: 0x00000000
kfdhdb.ub4spare[52]: 0 ; 0x1cc: 0x00000000
kfdhdb.ub4spare[53]: 0 ; 0x1d0: 0x00000000
kfdhdb.acdb.aba.seq: 0 ; 0x1d4: 0x00000000
kfdhdb.acdb.aba.blk: 0 ; 0x1d8: 0x00000000
kfdhdb.acdb.ents: 0 ; 0x1dc: 0x0000
kfdhdb.acdb.ub2spare: 0 ; 0x1de: 0x0000
通过对比我们可以发现与之前的raw5磁盘头的内容是一摸一样的。
6.由于之前破坏掉了raw5磁盘头信息，看看有啥报错
[oracle@axj-rac1 ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Wed Mar 9 15:09:17 2016
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup --重启数据库发现报错了
ORA-01078: failure in processing system parameters
ORA-01565: error in identifying file '+DATADG01/rac11g/spfilerac11g.ora'
ORA-17503: ksfdopn:2 Failed to open file +DATADG01/rac11g/spfilerac11g.ora
ORA-15077: could not locate ASM instance serving a required diskgroup
看看asm日志
SQL> ALTER DISKGROUP DATADG01 MOUNT
NOTE: cache registered group DATADG01 number=1 incarn=0xbec84ee5
NOTE: cache began mount (first) of group DATADG01 number=1 incarn=0xbec84ee5
Wed Mar 09 15:10:28 2016
ERROR: no read quorum in group: required 2, found 0 disks
NOTE: cache dismounting (clean) group 1/0xBEC84EE5 (DATADG01)
NOTE: messaging CKPT to quiesce pins Unix process pid: 3711, image: oracle@axj-rac1 (TNS V1-V3)
NOTE: dbwr not being msg'd to dismount
NOTE: lgwr not being msg'd to dismount
NOTE: cache dismounted group 1/0xBEC84EE5 (DATADG01)
NOTE: cache ending mount (fail) of group DATADG01 number=1 incarn=0xbec84ee5
NOTE: cache deleting context for group DATADG01 1/0xbec84ee5
GMON dismounting group 1 at 7 for pid 29, osid 3711
ERROR: diskgroup DATADG01 was not mounted
ORA-15032: not all alterations performed
ORA-15017: diskgroup "DATADG01" cannot be mounted
ORA-15063: ASM discovered an insufficient number of disks for diskgroup "DATADG01"
可以看到的是datadg01无法mount
通过asmcmd查看,datadg01磁盘组都没了
[grid@axj-rac1 trace]$ asmcmd
ASMCMD> lsdg
State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name
MOUNTED EXTERN N 512 4096 1048576 6024 5623 0 5623 0 Y OCR_VOTE/
三、修复磁盘头
方法一：kfed修复磁盘头
[grid@s1-11g dev]$
kfed repair /dev/raw/raw5
kfed repair /dev/raw/raw6
kfed repair /dev/raw/raw7
方法二: dd修复，用之前的备份
[grid@s1-11g dev]$
dd if=/backup/raw5 of=/dev/raw/raw5
dd if=/backup/raw6 of=/dev/raw/raw6
dd if=/backup/raw7 of=/dev/raw/raw7
方法三： 利用oracle的kfed工具来备份,格式是文本格式，恢复时使用kfed merge进去
备份：
kfed read /dev/raw/raw5 aunum=0 blknum=0 text=/home/oracle/raw5.txt
kfed read /dev/raw/raw6 aunum=0 blknum=0 text=/home/oracle/raw6.txt
kfed read /dev/raw/raw7 aunum=0 blknum=0 text=/home/oracle/raw7.txt
恢复：
kfed write /dev/raw/raw5 aunum=0 blknum=0 text=raw5.txt
kfed write /dev/raw/raw6 aunum=0 blknum=0 text=raw6.txt
kfed write /dev/raw/raw7 aunum=0 blknum=0 text=raw7.txt
这里我用的是方法一修复的
1.恢复完成后查看磁盘头信息：
[root@axj-rac1 oracle]# kfed read /dev/raw/raw5 aun=0 blkn=0|grep kfbh.type
kfbh.type: 1 ; 0x002: KFBTYP_DISKHEAD
2.然后成功mount磁盘组
3.查看dg状态可以看到是mounted状态
ASMCMD> lsdg
State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name
MOUNTED EXTERN N 512 4096 1048576 10024 6581 0 6581 0 N DATADG01/
MOUNTED EXTERN N 512 4096 1048576 6024 5623 0 5623 0 Y OCR_VOTE/
可以看到datadg02已结mount了
3.重新查询磁盘组以及磁盘信息
col group_number format a30
col disk_number format a30
col name format a30
col header_status format a30
col path format a30
col group_number clear
col disk_number clear
set linesize 200 pagesize 2000
SQL>select group_number,disk_number,name,header_status,path from v$asm_disk;
GROUP_NUMBER DISK_NUMBER NAMEHEADER_STATUS PATH
------------ ----------- -----------------------------
1 1 DATADG01_0001MEMBER /dev/raw/raw6
1 0 DATADG01_0000MEMBER /dev/raw/raw5
2 1 OCR_VOTE_0001MEMBER /dev/raw/raw2
2 0 OCR_VOTE_0000MEMBER /dev/raw/raw1
1 2 DATADG01_0002MEMBER /dev/raw/raw7
2 2 OCR_VOTE_0002MEMBER /dev/raw/raw3
可以看到所有状态已经正常,数据库也正常启动。