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The ASM disk header can not be recovered (Help Me)

The ASM disk header can not be recovered (Help Me)

Please help us, the database is critical for the business.
 
In asmlib two disks had been configured to point to the same disk multipath /dev/mapper/mpathc1 (DATA03) and /dev/mapper/mpathc (FRA), when creating FRA diskgroup the DATA03 was lost. 
 
Here the sequence events:
 
1.- A new FRA diskgroup was created using the disk /dev/mapper/mpathc that appeared as available and this action corrupted the disk header /dev/mapper/mpathc1 that belongs to the diskgroup DATA03.
2.- We tried to recover the header, recreating the DATA03 diskgroup and with it we only got to have the diskgroup mounted but without data. We understand that the disc was reincarnated as if it were a new one.
 
 
SQL> CREATE DISKGROUP FRA EXTERNAL REDUNDANCY DISK 'ORCL:DISK01' SIZE 102400M 
ATTRIBUTE 'compatible.asm'='12.2.0.1','au_size'='4M' /* ASMCA */ 
2018-01-15T21:06:06.488215-05:00 
 
ORCL:DISK01 --> /dev/mapper/mpathc 
ORCL:DATA3 --> /dev/mapper/mpathc1 
 
Both of them is the same disk.
 
The Database was installed in ORCL:DATA1, ORCL:DATA2, ORCL:DATA3 and ORCL:DATA4 
 
The other disk of ASMLib ORCL:DISK01, ORCL:DISK02 and ORCL:DISK03 were configure over /dev/mapper/mpath* 
 
We need to recover ORCL:DATA3 --> /dev/mapper/mpathc1) that was updated by (ORCL:DISK01 --> /dev/mapper/mpathc) 
 
Lists ASMLIb: 
 
# oracleasm listdisks | xargs -i oracleasm querydisk -d {} 
Disk "DATA1" is a valid ASM disk on device [253,8] 
Disk "DATA2" is a valid ASM disk on device [253,7] 
Disk "DATA4" is a valid ASM disk on device [253,4] 
Disk "DISK01" is a valid ASM disk on device [253,2] 
Disk "DISK03" is a valid ASM disk on device [253,3] 
Disk "DISK04" is a valid ASM disk on device [253,5] 
 
# oracleasm listdisks | xargs -i oracleasm querydisk -p {} 
Disk "DATA1" is a valid ASM disk 
/dev/sdh1: LABEL="DATA1" TYPE="oracleasm" 
/dev/sdi1: LABEL="DATA1" TYPE="oracleasm" 
/dev/mapper/mpatha1: LABEL="DATA1" TYPE="oracleasm" 
Disk "DATA2" is a valid ASM disk 
/dev/sdf1: LABEL="DATA2" TYPE="oracleasm" 
/dev/sdg1: LABEL="DATA2" TYPE="oracleasm" 
/dev/mapper/mpathb1: LABEL="DATA2" TYPE="oracleasm" 
Disk "DATA4" is a valid ASM disk 
/dev/sdb1: LABEL="DATA4" TYPE="oracleasm" 
/dev/sdc1: LABEL="DATA4" TYPE="oracleasm" 
/dev/mapper/mpathd1: LABEL="DATA4" TYPE="oracleasm" 
Disk "DISK01" is a valid ASM disk 
/dev/mapper/mpathc: LABEL="DISK01" TYPE="oracleasm" PTTYPE="dos" 
Disk "DISK03" is a valid ASM disk 
/dev/mapper/mpathb: LABEL="DISK03" TYPE="oracleasm" PTTYPE="dos" 
Disk "DISK04" is a valid ASM disk 
/dev/mapper/m 
 
Error Codes 
--------------------------------------------------- 
ORA-15196: invalid ASM block header [kfc.c:29767] [blk_kfbl] [4] [1] [257 != 1] ORA-15196: invalid ASM block header [kfc.c:29767] [blk_kfbl] [4] [1] [257 != 1] 
 
 
Answer:
 
  the data03 diskgroup has been reincarnated by rebuild diskgroup .  what we can do is we can scan the whole disk find out block fragment and merge them , then we can recover most of data.  But this service cost a lots of money.  Let me know your database size ,then we can have a price.