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Mounting Diskgroup Fails With ORA-15063 and V$ASM_DISK Shows PROVISIONED (Doc ID 1487443.1)

Symptoms

1. ASM is restarted and some ASM diskgroups will not be mounted with the following similar error.

SQL> alter diskgroup DATA mount;

alter diskgroup DATA mount

*

ERROR at line 1:

ORA-15032: not all alterations performed

ORA-15017: diskgroup “DATA” cannot be mounted

ORA-15063: ASM discovered an insufficient number of disks for diskgroup “DATA”

2. v$asm_disk view returns all ASM device information but v$asm_disk.header_status colume shows the status as

“PROVISIONED”.

SQL> select group_number gn,disk_number dn, mount_status, header_status,mode_status,state, total_mb,

free_mb, label, path from v$asm_disk order by group_number, disk_number;

GN DN MOUNT_STATUS HEADER_STATU MODE_STATUS STATE TOTAL_MB FREE_MB

LABEL PATH

0 0 CLOSED PROVISIONED ONLINE NORMAL 0 0

CRS ORCL:CRS

0 1 CLOSED PROVISIONED ONLINE NORMAL 0 0

DATA ORCL:DATA

3. kfed output for the device affected shows 0xaa55 on kfdhdb.acdb.ub2spare field ( 2 bytes at 510th location ).

Example>

$ kfed read /dev/oracleasm/disks/DATA

kfbh.endian: 1 ; 0x000: 0x01

kfbh.hard: 130 ; 0x001: 0x82

..

kfdhdb.acdb.ents: 0 ; 0x1dc: 0x0000

kfdhdb.acdb.ub2spare: 43605 ; 0x1de: 0xaa55

Cause

0xaa55 on little-endian server like Linux or 0x55aa on big-endain server like Sun Sparc indicates boot signature ( or

magic number ) on MBR (Master Boot Record ) Partition.

This issue could happen outside ASM when some tools on OS ( or human ) put partition information on the affected

device.

Solution

This situation can happen while the affected diskgroup is mounted and maintenance window needs to be scheduled to

repair the device header.

1. Shutdown ASM instance

2. Take a 1M dd backup just in case.

$ dd if=/dev/oracleasm/disks/DATA of=/tmp/DATA.dd bs=1M count=1

3. Repair the device header in the following way. Repeat the following example procedure for the all affected devices.

Check AU ( Allocation Unit ) size for the disk in the following way for aus option in kfed command .

$ kfed read /dev/oracleasm/disks/DATA | grep ausize

kfdhdb.ausize: 1048576 ; 0x0bc: 0x00100000

^^^^^^

If ASM version is 11.1.0.7 or above,

$ kfed repair /dev/oracleasm/disks/DATA aus=1048576

If ASM version is less than 11.1.0.7,

$ kfed read /dev/oracleasm/disks/DATA text=./DATA.kfed

$ kfed write /dev/oracleasm/disks/DATA CHKSUM=YES aus=1048576 text=./DATA.kfed

4. Startup ASM and mounte the affected diskgroup.

5. The procedure above only works with the symtom (0xaa55 on 510th location on device header ) described above.

And there are many other possibilities causing PROVISIONED status in which the procedure above may not work.

And note that if the procedure above does not resolve the issue, the corruption must have been spreaded to other

blocks beyond disk header. Contact Oracle Support for further investigation.