RAID 10 Question

[Adajer]

Is it possible to have RAID 10 with 2 Velociraptors 6gb/s as the read(0) drives and 2 640GB 7200RPM 3.0gb/s as the mirrored(1) drives?

edit: Only 2 6gb/s slots on motherboard.

[xopher]

That would be a JBOD.

You need all the same size disks to do a RAID.

[Icari]

You need all the same size disks to do a RAID.

or otherwise you dont have access to the extra hard drive space on the larger disks

[Evanos]

This configuration would be possible depending on the RAID controller. I haven't personally went with a RAID10 myself but have done a 0 and 5.

Generally it is not recommended to have drives of different size, but it is possible. All drives in the array will equal the size of the smallest drive, so in essence your 640s will become 600s. My biggest uncertainty would be the different sizes of the cache and read speed. Every RAID array that I have done those were all equal, so I did not look into that. I am sure you can use different sized discs though.

Also, if not enough 6GB SATA connectors is a problem there is an (expensive) option. But, I don't think this would be an issue with your setup.

[Adajer]

They have the same cache just different read speeds. I will probably just go with a RAID 0 and manually back up anything I would like backed up.

[Evanos]

They have the same cache just different read speeds. I will probably just go with a RAID 0 and manually back up anything I would like backed up.

Yeah, that is what I would have opted for personally. Would love to see those raptors on RAID0.

[levish]

Is it possible to have RAID 10 with 2 Velociraptors 6gb/s as the read(0) drives and 2 640GB 7200RPM 3.0gb/s as the mirrored(1) drives?

edit: Only 2 6gb/s slots on motherboard.

Most likely yes its possible,


What you are asking is not for RAID10, what you are asking is can you build one RAID0 array (stripe/performance) with the velociraptors and one RAID1 (mirrored/redundancy) array with the storage drives.

RAID10 is when you have 4 or more drives in one array (presented to the OS as a single drive). This type of array can only be built/expanded in pairs. RAID5 is another alternative that would give you more space at the cost of some more processing overhead.

Sticking with what you said, you would have no redundancy for the RAID0 array, you would have redundancy for the 640GB drives but redundancy doesn't mean you should not make backups of your data (lots non-technical of people think this).

What you are proposing is actually what I am doing myself with 2x RAID0 OCZ 120GB ssd's for the boot/applications and 2x 1TB Hitachi's RAID1 drives for Data.

If you are going through the effort of buying fast drives might want to just use a single SSD instead since it will match or exceed your RAID0 velociraptors at large file sizes and at small file sizes it will be orders of magnitude faster (around 20x faster on 4k random reads).

There were some specials going on for the Crucial C300 128GB drive for 249$ that will do up to 350MB/sec seq large file reads (if you have a SATA 6Gbps port connected) and "zomghax" speeds for random 4k reads. If you need more space then you'd be best served using 2x of them in RAID0 as the 256GB Drive isn't significantly faster but it is more than 2x as expensive

[Killgannon]

Raptors in RAID0 are FUN until one decides it hates life and kills itself, and its the older 36GB model and then WD sends youa 72GB model so your RAID0 is FUCKED OVER hurray!!! -.-;;