Recreating the failed diskgroup with the same name

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Not able to drop diskgroup
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[oracle@subdb01 ~]$ asmcmd umount FRA
ORA-15032: not all alterations performed
ORA-15001: diskgroup "FRA" does not exist or is not mounted (DBD ERROR: OCIStmtExecute)
[oracle@subdb01 ~]$ asmcmd dropdg -f -r FRA
ORA-15039: diskgroup not dropped
ORA-15063: ASM discovered an insufficient number of disks for diskgroup "FRA" (DBD ERROR: OCIStmtExecute)

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ERROR description
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Our disk headers were overwritten by mistake so it was complaining about duplicate paths

SQL> CREATE DISKGROUP FRA EXTERNAL REDUNDANCY DISK '/dev/oracleasm/disks/DISK01' ,
'/dev/oracleasm/disks/DISK02' , '/dev/oracleasm/disks/DISK03'
NOTE: Assigning number (5,0) to disk (/dev/oracleasm/disks/DISK01)
NOTE: Assigning number (5,1) to disk (/dev/oracleasm/disks/DISK02)
NOTE: Assigning number (5,2) to disk (/dev/oracleasm/disks/DISK03)
WARNING: detected duplicate paths to the same disk:
'/dev/oracleasm/disks/DISK06' and
'/dev/oracleasm/disks/DISK02'
More trace information dumped to '/oracle/app/diag/asm/+asm/+ASM1/trace/+ASM1_ora_8000.trc'
WARNING: detected duplicate paths to the same disk:
'/dev/oracleasm/disks/DISK09' and
'/dev/oracleasm/disks/DISK05'
More trace information dumped to '/oracle/app/diag/asm/+asm/+ASM1/trace/+ASM1_ora_8000.trc'
WARNING: detected duplicate paths to the same disk:
'/dev/oracleasm/disks/DISK07' and
'/dev/oracleasm/disks/DISK03'
More trace information dumped to '/oracle/app/diag/asm/+asm/+ASM1/trace/+ASM1_ora_8000.trc'
WARNING: detected duplicate paths to the same disk:
'/dev/oracleasm/disks/DISK08' and
'/dev/oracleasm/disks/DISK04'
More trace information dumped to '/oracle/app/diag/asm/+asm/+ASM1/trace/+ASM1_ora_8000.trc'
NOTE: erasing header on grp 5 disk FRA_0000
Thu Oct 25 21:51:04 2012
GMON dismounting group 5 at 422 for pid 51, osid 8000
NOTE: Disk in mode 0x8 marked for de-assignment
NOTE: Disk in mode 0x8 marked for de-assignment
NOTE: Disk in mode 0x8 marked for de-assignment
ERROR: diskgroup FRA was not created
ORA-15018: diskgroup cannot be created
ORA-15020: discovered duplicate ASM disk "FRA_0005"
ERROR: CREATE DISKGROUP FRA EXTERNAL REDUNDANCY DISK '/dev/oracleasm/disks/DISK01' ,
'/dev/oracleasm/disks/DISK02' , '/dev/oracleasm/disks/DISK03'

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Creating disk group with force option
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So as above disk 2,3,4,5 was showing overwritten with duplicate information

so to relebel them in ASMLIB please follow the below steps


Action Plan
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1. Relable the affected devices using the following command.

# /etc/init.d/oracleasm force-renamedisk /dev/oracleasm/disks/DISK02 DISK02
# /etc/init.d/oracleasm force-renamedisk /dev/oracleasm/disks/DISK03 DISK03
# /etc/init.d/oracleasm force-renamedisk /dev/oracleasm/disks/DISK04 DISK04
# /etc/init.d/oracleasm force-renamedisk /dev/oracleasm/disks/DISK05 DISK05

2. And run scandisks command from all nodes.


# /etc/init.d/oracleasm scandisks

3. Create DUMMY diskgroup with all 9 devices belonged to FRA diskgroup in the following way.

SQL> CREATE DISKGROUP DUMMY EXTERNAL REDUNDANCY DISK
'/dev/oracleasm/disks/DISK01' ,
'/dev/oracleasm/disks/DISK02' force,
'/dev/oracleasm/disks/DISK03' force,
'/dev/oracleasm/disks/DISK04' force,
'/dev/oracleasm/disks/DISK05' force,
'/dev/oracleasm/disks/DISK06' force,
'/dev/oracleasm/disks/DISK07' force,
'/dev/oracleasm/disks/DISK08' force,
'/dev/oracleasm/disks/DISK09' force;

4. Once DUMMY diskgroup can be created properly, drop it.
SQL> drop diskgroup DUMMY including contents;

5. And then recreate FRA with the following command.
SQL> CREATE DISKGROUP FRA EXTERNAL REDUNDANCY DISK
'/dev/oracleasm/disks/DISK01' ,
'/dev/oracleasm/disks/DISK02' ,
'/dev/oracleasm/disks/DISK03' ,
'/dev/oracleasm/disks/DISK04' ,
'/dev/oracleasm/disks/DISK05' ,
'/dev/oracleasm/disks/DISK06' ,
'/dev/oracleasm/disks/DISK07' ,
'/dev/oracleasm/disks/DISK08' ,
'/dev/oracleasm/disks/DISK09' ;