remove disk from RAID 5

[Gavoz]

Hi i have a SmartArray 641 controller configured with 4x36Gb in raid 5.
Here is my current configuration:

Controller Smart Array 642 in Slot 1
SCSI parallela Array A

-36.4 GB SCSI, ID SCSI 0
36.4 GB SCSI, ID SCSI 1
36.4 GB SCSI, ID SCSI 2
36.4 GB SCSI, ID SCSI 3
Logic unit 1 ( 69455 MB, RAID 5 )
Unused space, 46304 MB

can i remove one disk from array without loose data/OS?
I need it cause I have 3 new 72Gb HD that I want to install and configure as a 2 array in RAID5 but I have no space in server, 4 of 6 slot are busy.
Thanks in advance,

-
Andrea

[ramesh_naik_]

Hi Andrea,

Looking at the current configuration of the array, it seems like you have configured an online spare option.

If there is a requirement for 2 array in RAID 5, then we need to remove the online spare option from the Array Configuration Utility and then install a new RAID 5 with the 3 other hdds of 72GB.

Please refer to the documentation of the ACU from here:
http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00709035/c00709035.pdf?jumpid=reg_R1002_USEN

Hope this explains!!!

Regards,
rmn

[Gavoz]

Hi, I don't have the option to remove spare disk. So I think that I have all 4 disk configured in RAID5 array.Attached a snapshot of the current configuration/view.
Thanks,

-
Andrea

[ramesh_naik_]

Hi Andrea,

Since there is an Unused space, 46304 MB in the array, we need to first identify which is the unused space.

By the observation of the ACU, I think you have already upgraded the hard drives before and hence there was unused space left.

For RAID 5 the minimum number of hard drives required are 3. Hence one of the hard drives have been assigned to be the online spare.

However since I was not able to translate Italian I was not able to figure out whether the online spare is configured or not.

You can check the configuration wizard to add or remove the online spare if it is configured with one.

Once the online spare is removed, then you can create another RAID 5 array with another 3 hard drives.

Regards,
rmn

[Gavoz]

Hi, if I run the configuration wizard to view what I can do with the configured array I can't see anything related to spare (remove or other option), so I'm unable to remove the spare disk cause I think it's not configured as spare...

[ramesh_naik_]

Hi Andrea,

Then the possible solution I can think of would be to take a backup of the existing RAID array and rebuild the array with 3 hard drives to avoid any data loss on the drives in case you want to use 3 hard drives in an array.

But not totally convinced about the unused space in the RAID.

Any idea why there is an Unused space of 46304 MB in the array?

Regards,
rmn