How many disks can you have in a raid 5

Or, contact us with your questions. RAID 0 is used by those wanting the most speed out of two or more drives. Because the data is split across both drives, the speed of data reading and writing increases as more disks are added. Every drive has a limited lifespan and each disk adds another point of failure to the RAID. RAID 1 mirroring Mirroring creates an exact duplicate of a disk.

Every time you write information to one drive, the exact information is written to the other drive in your mirror. Important files accounting, financial, personal records are commonly backed up with a RAID 1. This is the safest option for your data. If one drive is lost, your data still exists in its complete form, and takes no time to recover. Your investment in data safety increases your drive costs since each RAID 1 volume requires two drives.

RAID 3 A rare implementation of parity striping. Its limitation is that it cannot service multiple requests. RAID 4 A rare implementation of parity striping at the block level with an entire disk dedicated to parity data. ProMAX vs. Editshare ProMAX vs. How many drives can fail in a RAID configuration? Recent Topics Archive.

Subscribe to Updates. All Rights Reserved. It's a parity RAID, so it has the same performance penalties for rebuilds, expansions, and restripes as RAID5, it just lets you grow larger in a safer way. There isn't really a clear limit on the number of disks in RAID 5 per se. The limits you'll meet are typically related to RAID 5's relatively poor write performance , and limitations imposed elsewhere RAID controller, your own organization of data etc.

Having said that, with disks in use you're close to upper bound on the common RAID 5 deployments. I'm more puzzled by your choice to keep one big array for all this. If you don't have an need for a single block of space larger than a 3 disk array, then there is no reason to cram all 6 disks into 1 raid. You're not going to gain anything in performance or over-all space, and, given a two disk failure, you're probably going to be in a better place.

Dayton Brown: The total space will be the same The difference is, RAID5 only allows for 1 parity drive, whether there are 3 drives in the RAID or , so splitting the drives into manageable groups adds protection against multiple failures.

Even if you lost 3 disks, for example, you'd only lose half of your data. If you moved to RAID6, a six disk array would make more sense, because you could lose two and be okay. But most people jump straight to RAID10, and skip 6. How much space do your NEED? Any number of disks in a RAID 5 array is too many disks.

You've invested in expensive hardware to build a SAN; arrays, switches, fibre, training etc. Then you've put in pretty fast relatively expensive disks. Furthermore you want to put VMs on it. With this investment and usage it looks like you want to make it as fast as you can so your VM users don't complain about performance. So why touch RAID 5 at all? With RAID5, you want to keep your disk count as low as possible, while still providing the necessary space.

A hot spare, per RAID5 array , is recommended to ensure reliability. RAID6 is really a much better idea for a future addition. Lots of folks , in fact, recommend this , especially in this day and age. I think my adaptec limits a single array to 32 discs. I don't have a suggestion as to the array size but I would suggest adding a second hot spare or making this RAID 6.

The time required to rebuild an array of that size increases the risk of a drive failing before the array has been rebuilt. If you have any doubts about the RAID 5 array and number of disks needed for the setup, then go through this link. Sign up to join this community. The best answers are voted up and rise to the top.

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