Resizing Oracle ASM disks

Today I though I would share with how easy it is to resize Oracle ASM volumes with Pure Storage.

Ok, lets first check the Oracle ASM disk sizes using ‘asmcmd -p’


As you can see from the above, I have 3 volumes each of 100GB, for this test let’s increase them all to 1TB using the purevol command from with the CLI.


Great, my volumes have now al been resized, I could have achieved the same results with the Pure UI or Web Services, but that’s something for another day.

Linux device rescan

Ok, we now need to let Linux and Oracle know about our resized volumes.

As root rescan the SCSI devices to identify which volumes which have been resized using: -s

Use ‘multipathd -k ‘resize map ‘ to resize the multipath devices e.g.

multipathd -k'resize map slob-data'

Before you moving onto resizing the Oracle ASM disk groups check your updated multi path configuration with ‘multipath -ll’, look for your device name and size e.g.

slob-data (3624a937050c939582b0f46c000059779) dm-5 PURE,FlashArray      size=1.0T features='0' hwhandler='0' wp=rw
`-+- policy='queue-length 0' prio=1 status=active

Oracle ASM resize

As your ‘grid’ user connect as sysasm from sqlplus e.g. sqlplus / as sysasm and perform ‘alter disk group <dg_name> resize all’


Great, job done, but before we more on let’s check out work first using sqlplus as sysasm

SQL>  select name, total_mb/(1024) "Total GiB" from v$asm_diskgroup;
NAME                           Total GiB
------------------------------ ----------
CONTROL_REDO                   1024
FRA                            1024
DATA                           1024

And, now with the ASM command line utility ‘asmcmd’


Or if you prefer the ASM UI ‘asmca’.


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