[轉載] ASM Disk Header 備份與還原

Ref:

http://www.cnblogs.com/lhrbest/articles/5641778.html

http://www.askmaclean.com/page/118?m=o

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1. dd備份恢復

備份voting disk：

dd if=/dev/raw/raw3 of=/tmp/votedisk_lhr.bak bs=1024k count=4

恢復voting disk：

dd if=/tmp/votedisk_lhr.bak of=/dev/raw/raw3 bs=1024k count=4

註：Oracle  11g 不推薦使用dd來進行ASM Header備份恢復，而改採用MD_Backup/ MD_restore指令進行 ;  ASM Disk Header一般是前4K

2. kfed恢復ASM Disk Header

dd if=/dev/rhdisk2 of=/asm_rhdisk2_dd.bak bs=1024 count=4

dd if=/dev/zero of=/dev/rhdisk2 bs=1024 count=4

kfed repair /dev/rhdisk2

關於kfed、kfod、amdu的更多內容可以參考：http://blog.itpub.net/26736162/viewspace-1694198/

http://blog.itpub.net/26736162/viewspace-1694199/

3. md_backup和md_restore ASM Disk Header (11g 以後可以透過md_backup方式來備份ASM disk header)

asmcmd md_backup /oracle/app/11.2.0/tmp/asm_md_backup.bak

#坊間謠傳ASM Disk Header為4K , 請在您的test environment實際測試過

dd if=/dev/rhdisk2 of=/asm_rhdisk2_dd.bak bs=1024k count=4

dd if=/dev/zero of=/dev/rhdisk2 bs=1024k count=4

crsctl stop has -f

crsctl start has

ASMCMD [+] > startup force nomount;

ASMCMD [+] > md_restore /oracle/app/11.2.0/tmp/asm_md_backup.bak

4.如果原本ASM DiskGroup是NORMAL Redunancy, 那麼單一disk corruption或壞掉, 可以透過以下方式修回:

@db1, db2
crsctl stop crs -f

@db1
crsctl start crs -excl -nocrs
dd if=/dev/zero of=/dev/mapper/votingdisk bs=1m count=10240
sqlplus / as sysasm
SQL> alter diskgroup VOTING add disk '/dev/mapper/votingdisk' force;
crsctl stop crs -f

@db1, db2
crsctl start crs

關於md_backup和md_restore更多測試內容可以參考：http://blog.itpub.net/26736162/viewspace-2121309/