Resize ASM disks in Azure (FG enabled cluster)
July 20, 2020 Leave a comment
1. If the node is a database node, stop all local database instances running on the node.
2. Stop database VM from Azure console. In azure you are not able to resize disks while VM is running, so we need to stop it first.
3. Increase all database disks belonging to the same diskgroup to the desired size. Make sure disks in the same diskgroup have the same sizes.
To resize disk, click VM -> Disks -> choose data disk (in my case 10GB disk is a DATA disk)

After clicking the above disk, you will be redirected to the following screen, choose Configuration -> enter desired disk size (in my case I’ve changed from 10 to 15) -> Save

4. Start the database node.
5. Repeat 1-4 steps for the next database nodes (no need to increase disks for quorum, it is only necessary for the database nodes)
6. Check new disk sizes:
If it is Fg cluster, Phys_GiB column must show increased size:
[root@rac1 ~]# flashgrid-dg show -G DATA
...
------------------------------------------------------------
FailGroup ASM_Disk_Name Drive Phys_GiB ASM_GiB Status
------------------------------------------------------------
RAC1 RAC1$LUN2 /dev/flashgrid/rac1.lun2 15 10 ONLINE
RAC2 RAC2$LUN2 /dev/flashgrid/rac2.lun2 15 10 ONLINE
RACQ RACQ$LUN3 /dev/flashgrid/racq.lun3 1 1 ONLINE
------------------------------------------------------------
In case it is a normal cluster, OS_MB must show increased size:
# su - grid
$ sqlplus / as sysasm
SQL> select TOTAL_MB/1024,OS_MB/1024 from v$asm_disk where GROUP_NUMBER=2 ;
TOTAL_MB/1024 OS_MB/1024
------------- ----------
10 15
10 15
1 1
7. Connect to the ASM from any database node and run:
# su - grid
$ sqlplus / as sysasm
SQL> ALTER DISKGROUP DATA RESIZE ALL;
The above command will resize all disks in the specified diskgroup based on their size returned by OS.
8. Check new sizes:
Fg cluster:
[root@rac1 ~]# flashgrid-dg show -G DATA
...
------------------------------------------------------------
FailGroup ASM_Disk_Name Drive Phys_GiB ASM_GiB Status
------------------------------------------------------------
RAC1 RAC1$LUN2 /dev/flashgrid/rac1.lun2 15 15 ONLINE
RAC2 RAC2$LUN2 /dev/flashgrid/rac2.lun2 15 15 ONLINE
RACQ RACQ$LUN3 /dev/flashgrid/racq.lun3 1 1 ONLINE
------------------------------------------------------------
Normal cluster:
SQL> select TOTAL_MB/1024,OS_MB/1024 from v$asm_disk where GROUP_NUMBER=2 ;
TOTAL_MB/1024 OS_MB/1024
------------- ----------
15 15
15 15
1 1
Phys_GiB and ASM_GiB should have the same increased size, which means disks are resized and you can use extended space.