Shrinking ASM disk

Question

I just tried to resize an ASM disk and although the feedback was 'successful', there doesn't appear to have been any change.
I was attempting to shrink disk DATA_0001 from 200G to 100G. Am I missing something obvious?
SQL> select group_number, name, path, os_mb, total_mb, free_mb from v$asm_disk;
GROUP_NUMBER NAME                 PATH                                OS_MB   TOTAL_MB    FREE_MB
          0                      /dev/iscsi/rman11                   20489          0          0
          0                      /dev/iscsi/rmanB11                 102398          0          0
          0                      /dev/iscsi/rman1                    20490          0          0
          0                      /dev/iscsi/vote3                      300          0          0
          0                      /dev/iscsi/vote1                      300          0          0
          0                      /dev/iscsi/rmanP11                 204805          0          0
          0                      /dev/iscsi/vote2                      300          0          0
          0                      /dev/iscsi/rmanP1                  204810          0          0
          0                      /dev/iscsi/rmanB1                  102405          0          0
          1 DATA_0000            /dev/iscsi/db1                      10245      10245      10109
          2 FRA_0000             /dev/iscsi/flshbk1                  20490      20490      20465
GROUP_NUMBER NAME                 PATH                                OS_MB   TOTAL_MB    FREE_MB
          2 FRA_0001             /dev/iscsi/flshbkR1                409605     409605     409262
          1 DATA_0001            /dev/iscsi/dbR1                    204810     204810     202297
13 rows selected.
SQL> alter diskgroup data resize disk 'data_0001' size 100g;
Diskgroup altered.
SQL> select group_number, name, path, os_mb, total_mb, free_mb from v$asm_disk;
GROUP_NUMBER NAME                 PATH                                OS_MB   TOTAL_MB    FREE_MB
          0                      /dev/iscsi/rman11                   20489          0          0
          0                      /dev/iscsi/rmanB11                 102398          0          0
          0                      /dev/iscsi/rman1                    20490          0          0
          0                      /dev/iscsi/vote3                      300          0          0
          0                      /dev/iscsi/vote1                      300          0          0
          0                      /dev/iscsi/rmanP11                 204805          0          0
          0                      /dev/iscsi/vote2                      300          0          0
          0                      /dev/iscsi/rmanP1                  204810          0          0
          0                      /dev/iscsi/rmanB1                  102405          0          0
          1 DATA_0000            /dev/iscsi/db1                      10245      10245      10004
          2 FRA_0000             /dev/iscsi/flshbk1                  20490      20490      20465
GROUP_NUMBER NAME                 PATH                                OS_MB   TOTAL_MB    FREE_MB
          2 FRA_0001             /dev/iscsi/flshbkR1                409605     409605     409262
          1 DATA_0001            /dev/iscsi/dbR1                    204810     204810     202402
13 rows selected.The free_mb seems to have increased, but otherwise I can't see the effect of my change. Maybe I'm looking in the wrong place??
I tried restarting the ASM instance but it made no difference.
After resizing the disk in ASM I shrunk the disk volume in our storage array. ASM was of course down at the time.
When I attempted to restart ASM I saw this ...
SQL> startup
ASM instance started
Total System Global Area  283930624 bytes
Fixed Size                  2158992 bytes
Variable Size             256605808 bytes
ASM Cache                  25165824 bytes
ORA-15032: not all alterations performed
ORA-15036: disk '/dev/iscsi/dbR1' is truncatedNone of my diskgroups are mounted ...
SQL> select group_number, name, state from v$asm_diskgroup;
GROUP_NUMBER NAME            STATE
          0 DATA            DISMOUNTED
          0 FRA             DISMOUNTEDHere's the messages from the ASM instance alert log ...
SQL> ALTER DISKGROUP ALL MOUNT
NOTE: cache registered group DATA number=1 incarn=0x5f5e3343
NOTE: cache began mount (not first) of group DATA number=1 incarn=0x5f5e3343
NOTE: cache registered group FRA number=2 incarn=0x5f5e3344
NOTE: cache began mount (not first) of group FRA number=2 incarn=0x5f5e3344
WARNING::ASMLIB library not found. See trace file for details.
NOTE: Assigning number (1,0) to disk (/dev/iscsi/db1)
NOTE: cache dismounting group 1/0x5F5E3343 (DATA)
NOTE: dbwr not being msg'd to dismount
NOTE: lgwr not being msg'd to dismount
NOTE: cache dismounted group 1/0x5F5E3343 (DATA)
NOTE: cache ending mount (fail) of group DATA number=1 incarn=0x5f5e3343
kfdp_dismount(): 1
kfdp_dismountBg(): 1
NOTE: De-assigning number (1,0) from disk (/dev/iscsi/db1)
ERROR: diskgroup DATA was not mounted
NOTE: Assigning number (2,1) to disk (/dev/iscsi/flshbkR1)
NOTE: Assigning number (2,0) to disk (/dev/iscsi/flshbk1)
NOTE: cache dismounting group 2/0x5F5E3344 (FRA)
NOTE: dbwr not being msg'd to dismount
NOTE: lgwr not being msg'd to dismount
NOTE: cache dismounted group 2/0x5F5E3344 (FRA)
NOTE: cache ending mount (fail) of group FRA number=2
incarn=0x5f5e3344
kfdp_dismount(): 2
kfdp_dismountBg(): 2
NOTE: De-assigning number (2,0) from disk (/dev/iscsi/flshbk1)
NOTE: De-assigning number (2,1) from disk (/dev/iscsi/flshbkR1)
ERROR: diskgroup FRA was not mounted
ORA-15032: not all alterations performed
ORA-15036: disk '/dev/iscsi/dbR1' is truncated
ERROR: ALTER DISKGROUP ALL MOUNTAny clues?
Thanks,
Steve

Answer 1

Thanks Markus. I changed the size of the volume back to the original and was able to restart the ASM instances on both nodes. I confirmed it saw the size as the original 200G.
I then shut down ASM on the second node and issued the alter on the first node. Here's what happened ...
SQL> select group_number, name, path, os_mb, total_mb, free_mb from v$asm_disk order by name;
GROUP_NUMBER NAME       PATH                                OS_MB   TOTAL_MB    FREE_MB
           1 DATA_0000  /dev/iscsi/db1                      10245      10245      10004
           1 DATA_0001  /dev/iscsi/dbR1                    204810     204810     202402
           2 FRA_0000   /dev/iscsi/flshbk1                  20490      20490      20465
           2 FRA_0001   /dev/iscsi/flshbkR1                409605     409605     409262
           0            /dev/iscsi/rman1                    20490          0          0
           0            /dev/iscsi/rmanP1                  204810          0          0
           0            /dev/iscsi/rmanB1                  102405          0          0
           0            /dev/iscsi/rmanP11                 204805          0          0
           0            /dev/iscsi/rmanB11                 102398          0          0
           0            /dev/iscsi/rman11                   20489          0          0
10 rows selected.
SQL> alter diskgroup data resize disk 'data_0001' size 100g;
alter diskgroup data resize disk 'data_0001' size 100g
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15130: diskgroup "DATA" is being dismounted
ORA-15066: offlining disk "DATA_0001" may result in a data lossHere's the details from the alert log ...
SQL> alter diskgroup data resize disk 'data_0001' size 100g
NOTE: requesting all-instance membership refresh for group=1
WARNING: cache read a corrupted block gn=1 dsk=1 blk=257 from disk 1
NOTE: a corrupted block was dumped to /var/oracle/diag/asm/+asm/+ASM1/trace/+ASM1_ora_5295.trc
ERROR: cache failed to read gn=1 dsk=1  blk=257 from disk(s): 1
ORA-15196: invalid ASM block header [kfc.c:9133] [endian_kfbh] [2147483649] [257] [0 != 1]
System State dumped to trace file /var/oracle/diag/asm/+asm/+ASM1/trace/+ASM1_ora_5295.trc
NOTE: cache initiating offline of disk 1  group 1
WARNING: initiating offline of disk 1.3688884620 (DATA_0001) with mask 0x7e
NOTE: initiating PST update: grp = 1, dsk = 1, mode = 0x15
kfdp_updateDsk(): 14
Thu May 07 15:45:38 2009
kfdp_updateDskBg(): 14
ERROR: too many offline disks in PST (grp 1)
Thu May 07 15:45:38 2009
NOTE: halting all I/Os to diskgroup DATA
Thu May 07 15:45:38 2009
SQL> alter diskgroup DATA dismount force
NOTE: active pin found: 0x0x6ddf6060
NOTE: active pin found: 0x0x6ddf6168
ERROR: ORA-15130 signalled during resize of diskgroup DATA
Thu May 07 15:45:38 2009
NOTE: membership refresh pending for group 1/0xdc0f1999 (DATA)
kfdp_query(): 15
kfdp_queryBg(): 15
SUCCESS: refreshed membership for 1/0xdc0f1999 (DATA)
ERROR: ORA-15130 thrown in RBAL for group number 1
Errors in file /var/oracle/diag/asm/+asm/+ASM1/trace/+ASM1_rbal_5202.trc:
ORA-15130: diskgroup "DATA" is being dismounted
Errors in file /var/oracle/diag/asm/+asm/+ASM1/trace/+ASM1_rbal_5202.trc:
ORA-15130: diskgroup "DATA" is being dismounted
ORA-15032: not all alterations performed
ORA-15130: diskgroup "DATA" is being dismounted
ORA-15066: offlining disk "DATA_0001" may result in a data loss
ERROR: alter diskgroup data resize disk 'data_0001' size 100g
NOTE: cache dismounting group 1/0xDC0F1999 (DATA)
NOTE: dbwr not being msg'd to dismount
Thu May 07 15:45:41 2009
Dirty detach reconfiguration started (old inc 6, new inc 6)
List of nodes:
0
Global Resource Directory partially frozen for dirty detach
* dirty detach - domain 1 invalid = TRUE
10 GCS resources traversed, 0 cancelled
Dirty Detach Reconfiguration complete
Thu May 07 15:45:41 2009
freeing rdom 1
Thu May 07 15:45:41 2009
WARNING: dirty detached from domain 1
NOTE: cache dismounted group 1/0xDC0F1999 (DATA)
kfdp_dismount(): 16
kfdp_dismountBg(): 16
NOTE: De-assigning number (1,0) from disk (/dev/iscsi/db1)
NOTE: De-assigning number (1,1) from disk (/dev/iscsi/dbR1)
SUCCESS: diskgroup DATA was dismounted
SUCCESS: alter diskgroup DATA dismount force
ERROR: PST-initiated MANDATORY DISMOUNT of group DATA
Thu May 07 15:46:06 2009
SQL> alter diskgroup data resize disk 'data_0001' size 100g
ORA-15032: not all alterations performed
ORA-15001: diskgroup "DATA" does not exist or is not mounted
ERROR: alter diskgroup data resize disk 'data_0001' size 100gLooks like my earlier attempt has indeed screwed up something so even though the instances start OK and mount the diskgroup, I think there's a fair chance something would go splat sooner rather than later.
As this is a test database, I think I'll cut my losses and rebuild the diskgroup then restore it from backup. I'm assuming the effort involved in correcting the corruption will be greater than rebuilding and restoring.
Do you agree with this?
Then I'll try again and hopefully get it right.
Thanks for your help!!!
Steve