topic Re: Adding drives to array in Disk Enclosures

Adding drives to array

Reg Cooper — Wed, 08 Jun 2005 09:57:17 GMT

I have recently purchased 2 - 72 Gig SCSI drives for our DL-580 server.
I have also purchased 2 - 72 Gig SCSI drives for our Proliant 3000 server.
In the DL-580 we have a raid with 6-18.2 Gig drives as well as a spare.
We have 2-36.4 Gig drives in the 3000 with one spare as well.
We need to extend the drive space on both of these servers.
My question is...what is the best way to expand these arrays? Can I extend the existing arrays with these larger sized drives?
Do I have to create new arrays with these 72 Gig drives?
What would be the best sollution for these 4 new drives that I purchased?
Any help is appreciated.

Note: The DL580 is our Oracle database. The proliant is our file server.

Re: Adding drives to array

Leif Halvarsson_2 — Wed, 08 Jun 2005 10:19:08 GMT

Hi,

Normally it is not a good idea to mix drives of different sizes in the same disk group (or array). Either you can't utilize the full capacity of the larger drives or, the I/O load (on the larger disks) will be higher.

The best solution is to use disks of equal size in each group but, in your case you may need to move disks between the two servers (and, backup/restore all data).

Re: Adding drives to array

Timothy Cusson — Fri, 10 Jun 2005 14:22:14 GMT

First to confirm your configuration...

DL-580
2 x 18GB disks RAID1 System (18GB useable)
4 x 18GB disks RAID5 Oracle (54GB useable)
1 x 18GB disk SPARE = 7 total

P-3000
2 x 36GB disks RAID1 System & Data (36GB Useable)

=========================================
DL-580
Add four 72GB disks, create three member RAID5 with one 72GB spare, NOTE: The 72GB disk can be a spare for the 18GB disk, result...

2 x 18GB disks RAID1 System ( 18GB useable)
3 x 72GB disks RAID5 Oracle (144GB useable)
1 x 72GB disk SPARE = 6 physical disks total

P-3000
Add five 18GB disks from DL-580, create RAID5 with one 18GB spare, result...

2 x 36GB disks RAID1 System & Data ( 36GB Useable)
4 x 18GB disks RAID5 Data ( 54GB Useable)
1 x 18GB disk SPARE = 7 physical disks total