8x 500gb Disks SAN - 2 LUNs, Which RAID ?

[bonald]

I am debating over which RAID I will be using on our new 8 disks SAN.

I have 8 VM pretty much idling, and 4 VM more busy.

Which of these solutions you think will be the best,

RAID5 on 4 disks for my 8 idling VM +

RAID10 on 4 disk for my 4 busy VM

OR

Two RAID5 of 4 disks.

OR

One RAID10 of 8 disks.

I can't have a 8 disks RAID5 as vmware only see 2TB LUN.

I need around 2TB of usable storage.

Thanks!

[runclear]

I have 8 x 500 (7.200) drives in a OpenFiler setup as RAID-50 and the performance seems okay for now... and ive got close to 30VM's on it... some heavy I/O some not...

I always tend to setup my LUNS at 500GB....

Here at the office, i know we use 7+1 (Raid5) array's in our SAN's....

[RParker]

With only 8 disks, that limits your options. And you didn't mention if these were SATA or SAS.

I would go RAID 5 call it a day. You can debate performance to the nth degree and get 100 different opinions, but with only 8 disks, that's not going to really give anyone much to work with.

RAID 5 is how I would do it.

[mcowger]

Given that you cant do 1 big RAID5, and you know you only need 2TB or more useable, I would go something like:

1 RAID5 3+1 for your 'idle' VMs (1.5TB)

1 RAID10 2+2 for your 'hot' VMs (1TB).

That gives you good performance, meets your space needs and separates VM types.

Though, as Parker mentioned, it doesn't make a huge difference with only 8 disks.

--Matt

VCP, vExpert, Unix Geek

[RParker]

Given that you cant do 1 big RAID5, and you know you only need 2TB

Doh! I forgot to include the 2TB limitation..