Oracle ASM disk header destruction example

1.Create an external disk group DATA1

 

 

2. Backup disk header

[Root @ asm] # dd if =/dev/asm-diskf of =/asm/diskf1.bak bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 3.71699 seconds, 28.2 MB/s

3. Clear the disk header

[Root @ asm] # dd if =/dev/zero of =/dev/asm-diskf bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 0.0391271 seconds, 2.7 GB/s

4. Try to mount

SQL> alter diskgroup DATA1 mount;
Alter diskgroup DATA1 mount
*
ERROR at line 1:
ORA-15032: not all alterations saved Med
ORA-15017: diskgroup "DATA1" cannot be mounted
ORA-15063: ASM discovered an insufficient number of disks for diskgroup
"DATA1"

5. View alert logs

SQL> alter diskgroup DATA1 mount
NOTE: cache registered group DATA1 number = 3 incarn = 0xf1c89c27
NOTE: cache began mount (first) of group DATA1 number = 3 incarn = 0xf1c89c27
NOTE: Assigning number (3, 4) to disk (/dev/asm-diskj)
NOTE: Assigning number (3, 3) to disk (/dev/asm-diski)
NOTE: Assigning number (3, 2) to disk (/dev/asm-diskh)
NOTE: Assigning number (3, 1) to disk (/dev/asm-diskg)
Fri Apr 03 09:11:26 2015
ERROR: no read quorum in group: required 1, found 0 disks
NOTE: cache dismounting (clean) group 3/0xF1C89C27 (DATA1)
NOTE: messaging CKPT to quiesce pins Unix process pid: 7276, image: oracle @ asm (TNS V1-V3)
NOTE: dbwr not being msg 'd to dismount
NOTE: lgwr not being msg 'd to dismount
NOTE: cache dismounted group 3/0xF1C89C27 (DATA1)
NOTE: cache ending mount (fail) of group DATA1 number = 3 incarn = 0xf1c89c27
NOTE: cache deleting context for group DATA1 3/0xf1c89c27
Fri Apr 03 09:11:26 2015
NOTE: No asm libraries found in the system
ASM Health Checker found 1 new failures
GMON dismounting group 3 at 21 for pid 20, object ID 7276
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
NOTE: Disk in mode 0x8 marked for de-assignment
ERROR: diskgroup DATA1 was not mounted
ORA-15032: not all alterations saved Med
ORA-15017: diskgroup "DATA1" cannot be mounted
ORA-15063: ASM discovered an insufficient number of disks for diskgroup "data1"
ERROR: alter diskgroup DATA1 mount
Fri Apr 03 09:18:00 2015

6. Restore the disk header

[Root @ asm] # dd if =/asm/diskf1.bak of =/dev/asm-diskf bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 0.0391271 seconds, 2.7 GB/s

7. Try to mount the disk Group
SQL> alter diskgroup DATA1 mount;

Diskgroup altered.

2. NORMAL

1. Create a normal disk group DATA2

2. Backup disk header

[Root @ asm] # dd if =/dev/asm-diskf of =/asm/diskf2.bak bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 0.187849 seconds, 558 MB/s

3. Damage the disk header

[Root @ asm] # dd if =/dev/zero of =/dev/asm-diskf bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 0.0262667 seconds, 4.0 GB/s

4. View the disk group status
SQL> select group_number, name, state, type from v $ asm_diskgroup;

GROUP_NUMBER NAME STATE TYPE
-----------------------------------------------------------
1 DATA MOUNTED NORMAL
2 ORADATA MOUNTED EXTERN
3 DATA2 MOUNTED NORMAL

5. Dismount the disk Group

SQL> alter diskgroup data2 dismount;

Diskgroup altered.

6. Try to mount the disk Group

SQL> alter diskgroup data2 mount;
Alter diskgroup data2 mount
*
ERROR at line 1:
ORA-15032: not all alterations saved Med
ORA-15040: diskgroup is incomplete.
ORA-15042: ASM disk "0" is missing from group number "3"

7. View alert logs

SQL> alter diskgroup data2 mount
NOTE: cache registered group DATA2 number = 3 incarn = 0x62589c78
NOTE: cache began mount (first) of group DATA2 number = 3 incarn = 0x62589c78
NOTE: Assigning number (3, 4) to disk (/dev/asm-diskj)
NOTE: Assigning number (3, 3) to disk (/dev/asm-diski)
NOTE: Assigning number (3, 2) to disk (/dev/asm-diskh)
NOTE: Assigning number (3, 1) to disk (/dev/asm-diskg)
Fri Apr 03 09:33:36 2015
NOTE: group DATA2: updated PST location: disk 0001 (PST copy 0)
NOTE: group DATA2: updated PST location: disk 0002 (PST copy 1)
NOTE: group DATA2: updated PST location: disk 0003 (PST copy 2)
NOTE: GMON heartbeating for grp 3
GMON querying group 3 at 38for pid 20, osid 7681
NOTE: Assigning number (3, 0) to disk ()
GMON querying group 3 at 39 for pid 20, object ID 7681
NOTE: cache dismounting (clean) group 3/0x62589C78 (DATA2)
NOTE: messaging CKPT to quiesce pins Unix process pid: 7681, image: oracle @ asm (TNS V1-V3)
NOTE: dbwr not being msg 'd to dismount
NOTE: lgwr not being msg 'd to dismount
NOTE: cache dismounted group 3/0x62589C78 (DATA2)
NOTE: cache ending mount (fail) of group DATA2 number = 3 incarn = 0x62589c78
NOTE: cache deleting context for group DATA2 3/0x62589c78
GMON dismounting group 3 at 40 for pid 20 and osid 7681
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
NOTE: Disk in mode 0x8 marked for de-assignment
NOTE: Disk in mode 0x8 marked for de-assignment
ERROR: diskgroup DATA2 was not mounted
ORA-15032: not all alterations saved Med
ORA-15040: diskgroup is incomplete.
ORA-15042: ASM disk "0" is missing from group number "3"
ERROR: alter diskgroup data2 mount
Fri Apr 03 09:33:43 2015
ASM Health Checker found 1 new failures
Fri Apr 03 09:39:05 2015

8. Restore the disk header

[Root @ asm] # dd if =/asm/diskf2.bak of =/dev/asm-diskf bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 0.095314 seconds, 1.1 GB/s

9. Try mounting the disk again.
SQL> alter diskgroup data2 mount;

Diskgroup altered.

3. Create a HIGH disk group DATA3

2. Backup disk header

[Root @ asm] # dd if =/dev/asm-diskf of =/asm/diskf3.bak bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 0.171521 seconds, 611 MB/s

3. Clear the disk header

[Root @ asm] # dd if =/dev/zero of =/dev/asm-diskf bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 0.0213577 seconds, 4.9 GB/s

4. View the disk group status

SQL> select group_number, name, state, type from v $ asm_diskgroup;

GROUP_NUMBER NAME STATE TYPE
-----------------------------------------------------------
1 DATA MOUNTED NORMAL
2 ORADATA MOUNTED EXTERN
3 DATA3 MOUNTED HIGH

5. Dismount the disk group DATA3

SQL> alter diskgroup data3 dismount;

Diskgroup altered.

6. Mount a disk

SQL> alter diskgroup data3 mount;
Alter diskgroup data3 mount
*
ERROR at line 1:
ORA-15032: not all alterations saved Med
ORA-15040: diskgroup is incomplete.
ORA-15042: ASM disk "0" is missing from group number "3"

7. View alert logs

SQL> alter diskgroup data3 mount
NOTE: cache registered group DATA3 number = 3 incarn = 0x36489cbc
NOTE: cache began mount (first) of group DATA3 number = 3 incarn = 0x36489cbc
NOTE: Assigning number (3, 4) to disk (/dev/asm-diskj)
NOTE: Assigning number (3, 3) to disk (/dev/asm-diski)
NOTE: Assigning number (3, 2) to disk (/dev/asm-diskh)
NOTE: Assigning number (3, 1) to disk (/dev/asm-diskg)
Fri Apr 03 09:52:35 2015
WARNING: GMON has insufficient disks to maintain consensus. minimum required is 5
NOTE: group DATA3: updated PST location: disk 0001 (PST copy 0)
NOTE: group DATA3: updated PST location: disk 0002 (PST copy 1)
NOTE: group DATA3: updated PST location: disk 0003 (PST copy 2)
NOTE: group DATA3: updated PST location: disk 0004 (PST copy 3)
NOTE: group DATA3: updated PST location: disk 0001 (PST copy 0)
NOTE: group DATA3: updated PST location: disk 0002 (PST copy 1)
NOTE: group DATA3: updated PST location: disk 0003 (PST copy 2)
NOTE: group DATA3: updated PST location: disk 0004 (PST copy 3)
NOTE: GMON heartbeating for grp 3
GMON querying group 3 at 57 for pid 20, osid 8015
NOTE: group DATA3: updated PST location: disk 0001 (PST copy 0)
NOTE: group DATA3: updated PST location: disk 0002 (PST copy 1)
NOTE: group DATA3: updated PST location: disk 0003 (PST copy 2)
NOTE: group DATA3: updated PST location: disk 0004 (PST copy 3)
NOTE: Assigning number (3, 0) to disk ()
GMON querying group 3 at 58 for pid 20, object ID 8015
NOTE: group DATA3: updated PST location: disk 0001 (PST copy 0)
NOTE: group DATA3: updated PST location: disk 0002 (PST copy 1)
NOTE: group DATA3: updated PST location: disk 0003 (PST copy 2)
NOTE: group DATA3: updated PST location: disk 0004 (PST copy 3)
NOTE: cache dismounting (clean) group 3/0x36489CBC (DATA3)
NOTE: messaging CKPT to quiesce pins Unix process pid: 8015, image: oracle @ asm (TNS V1-V3)
NOTE: dbwr not being msg 'd to dismount
NOTE: lgwr not being msg 'd to dismount
NOTE: cache dismounted group 3/0x36489CBC (DATA3)
NOTE: cache ending mount (fail) of group DATA3 number = 3 incarn = 0x36489cbc
NOTE: cache deleting context for group DATA3 3/0x36489cbc
GMON dismounting group 3 at 59 for pid 20, osid 8015
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
NOTE: Disk in mode 0x8 marked for de-assignment
NOTE: Disk in mode 0x8 marked for de-assignment
ERROR: diskgroup DATA3 was not mounted
ORA-15032: not all alterations saved Med
ORA-15040: diskgroup is incomplete.
ORA-15042: ASM disk "0" is missing from group number "3"
ERROR: alter diskgroup data3 mount
Fri Apr 03 09:52:43 2015
ASM Health Checker found 1 new failures
Fri Apr 03 09:55:08 2015

8. Restore the disk header

[Root @ asm] # dd if =/asm/diskf3.bak of =/dev/asm-diskf bs = 1 M count = 100
100 + 0 records in
100 + 0 records out
104857600 bytes (105 MB) copied, 0.0911406 seconds, 1.2 GB/s

9. mount the disk again

SQL> alter diskgroup data3 mount;

Diskgroup altered.