I’ve never liked or trusted RAID 5 in the first place. No one has EVER said that 10 or 50 are implying “better” just because they are a higher number. I **do** run RAID 5 on reporting databases that handle massive read-only queries, but I can’t afford RAID 5 performance loss for a disk rebuild on a production machine, nor can I afford to take the chance at losing 2 disks holding critical data (whether I have backups or not). RAID 10 with 4 drives (you can have the fifth drive as hot spare) We always recommend utilizing RAID in conjunction with an offsite backup package for the best redundancy in your dedicated server. It is the best option for file and application servers that use several large drives for data storage. That also means that a minimum of 4 disks are required for RAID-10. RAID 6 is harder to define. next year, I’m going to build a server Keep in mind, a very important factor, when deciding on what RAID level to use, is the rebuild time and the RAID’s performance during rebuild. RAID offers you a variety of options to increase data redundancy and server performance, but it shouldn’t be considered an alternative to offsite data backup. RAID 0 helps to increase performance by striping volume data across multiple disk drives. For example: If a drive costs $1000US (and most are far less expensive than that) then switching from a 4 pair RAID10 array to a 5 drive RAID5 array will save 3 drives or $3000US. I appreciate you taking the time to post this information. Oh, you didn’t back it up to tape? The main downside of a RAID 10 array is that any drive segment is limited to the smallest drive in the array. Not all RAID configurations are created equal in terms of redundancy, speed, or disk size. The major limiting factor in data security is budget. RAID 1+0 doesn’t have 1 disk fault tolerance but 1 disk/span. I now run RAID 10 and 6 only and will probably go away from 6 in the future with the cost of drives going down. While I have your attention, can you talk to the following question I have: What do you think about the RAID hardware (or is it software?) If you can’t afford RAID 1+0 then go for RAID 1 at least even though there are no performance gains. Following are the key points to remember for RAID level 5. The possibility of a 2nd failure in the same mirror sets makes me reluctant to use RAID10. In virtually every other test RAID 10 has better performance. Check out some of our most popular blogs or click below to check out our YouTube Channel. Also, I’ve personally run over 10 different RAID-5 systems with all different kind of OS’s and HW’s and never had a complete failure. RAID 10 (Striping + Mirroring): RAID 10 combines the mirroring of RAID 1 with the striping of RAID 0. NO RAID5! Where are is the huge statistics of drive failures????? In about 7 years of experience with RAID, I’ve had two RAID 5 failures which were extremely problematic or costly to fix, so I don’t trust it any more. You will have entire rack redundancy. with SSD RAID 1 will be all we need and performance from 1+0 will not be necessary in my opinion. To repeat the point: So the RAID 5 will store 4 MB or raw data per drive whilst the RAID 10 is storing 6Mb. It seems to me that, in theory and for large arrays and assuming the hard drives themselves are the bottlenecks, RAID 6 is going to be better than RAID 10 is every way: faster (less duplication needed), safer (it can guarantee survival after two drives die whereas RAID 10 can’t; it can even correct small errors on the disk) and more space-efficient (less duplication needed). It’s got to touch hardware somewhere. * RAID 01 = a mirrored stripe set Have had several hard drives fail but never a failure of the RAID 5. Lets agree that RAID-5 is not safe enough on paper, how does it fare in REAL life? There is also RAID 50 to consider. The upside of this configuration is parity data provides data protection while the striping provides a performance boost. I have never seen it in my 6 years of Storage Admin across enterprise customers, ranging from banks to telecoms to govt. Though Flash, then RAID then single local disks might be the best order at the end of the day. WHAT WILL WE DO IF WE ARE USING HOTSPARE FOR BOTH RAID 50 AND RAID 10 THEN SIMULTANEOUSLY DRIVE FAILS FROM BOTH RAID LEVEL THEN THAT MOMENT HOW THE HOT SPARE WILL WORK.??? What sets this array apart is that it includes two independent sets of separately striped parity data. A RAID is a data storage technology that takes multiple physical disk drive components into a single logical unit. In terms of RAID, reading is extremely easy and writing is rather complex. RAID level 0 does not have the best read performance of all raid levels, since systems with redundancy have a … (it should be obvious that you would round up S/s), If S is 2 TB, s is 146 GB, and C is $500, RAID 5 would cost $7,500. I do use SCSI or SAS for all enterprise servers for speed with high-RPM spindles and cache. Learn More{{/message}}, {{#message}}{{{message}}}{{/message}}{{^message}}It appears your submission was successful. Obviously every case is different. Not all your information has same storage needs. If you of course have tens of thousands to spend then SAS is the way to go and don’t forget to replicate that information to another expensive array and then take intermittent snapshots as well. Bad IT consultants like you is what drives our business. Scott Adding a fourth HDD only cost $100. S = total storage area Eg. I’ve lost 2 Raid 5 arrays due to controller failures. This keeps it simple and straightforward with diagrams to boot. I have been in the IT industry for 12 years now. It can protect against two disk failure in each sub-array. There are cases, where RAID10 might be preferred and there are cases, where RAID5 (or any other RAID) might be better. storage virtualization technology which is used to organise multiple drives into various arrangments to meet certain goals like redundancy Absolutely! Consider a stripe size equal, or a fragment power of two of block/cluster size. Regardless if you use RAID0,1,5,10 or any combination, if you rely on them instead of a backup you’re going to have a bad time. Learn More{{/message}}, Next post: Debian Upgrade: GNU/Linux 4.0 Update 5 Available, Previous post: Seagate Barracuda: 1.5TB Hard Drive Launched, Linux Tips, Hacks, Tutorials, And Ideas In Blog Format, Laptop Battery Safety - protect yourself from flames, Howto Eclipse Test and Performance Tools Platform -…, MySQL Performance Tuning tips and techniques, Howto optimize Apache and PHP for performance, Optimizing Linux code, application and programs -…, CentOS / Red Hat Enterprise Linux 5.2 Poor NFS…, How To Measure Linux Filesystem I/O Performance With iozone, Performance Tuning for Linux swap partition. Additionaly it is more complex, which nets a more complex and possibly more buggy implementation, and less flexilbility with management. And when that happens, you are one unhappy camper. If you put unencrypted data in the cloud you are asking for issues, to those of you who do, good luck with that and I hope your resume is up to date. Another consideration is to look at host based striping at the same time. So I basically head towards Raid 5 (now 6 with the larger capacity issues) and then backups as well. Long answer: RAID 6 also offers excellent security, reliable storage, and good performance too. My company has done well over 100, probably closer to 200 Raid 5 implementations, at least another 30ish Raid 1’s. Similarly, when we talk about raid 60, which is known as raid 6+0 provides you a robust performance boost with a minimum of six hard drives working combined. Data is currently set up to autocreate multiple volumes for writing to BlueRay so at year end I can archive a nice set of BlueRay disks. RAID performance can be difficult to understand, especially as distinct RAID levels use varying techniques and behave rather differently in practice. 8TB I’m now starting to put in Raid 10 arrays for the virutal hosts. As for safety, RAID 10 definitely has the edge. Unless you’re a multi-million dollar enterprise and solve problems by throwing money at it, you will care about costs. Simply replace the failed drive and keep on going. RAID LEVEL 5. What is the cost of reduced performance and possibly reduced customer satisfaction? First of all, in a mission critical enterprise environment where cost really isn’t an issue, neither is your RAID array. So there’s a one in three chance that a 2nd drive failure results in no loss of data. Brilliant! hbspt.cta._relativeUrls=true;hbspt.cta.load(4290574, '72269fa9-be8e-4aa6-be31-a5f1f3aec6bf', {}); The best RAID for performance and redundancy. Highly recommended to those who have 4 or more hard drives in an enclosure (though it can be built with 3x). A few MS-Exchange and Oracle admins also recommended RAID 10 for both safety and performance over RAID 5. Besides, if you’re using SATA in the Enterprise, you deserve the high failure rate. RAID 5 costs more for write-intensive applications than RAID 1. We all KNOW that 10 is just a shortcut for saying 1+0/0+1. RAID 6 dedicates two disks’ worth of storage to redundancy. Thus, if there are three 250 GB hard drives and three 400 GB hard drives, then they contain two identical RAID 5 arrays with 500 GB of stored data and 250 GB of parity data. @David – There are situations where it is NOT advisable to deploy a parity based RAID. That said, I always have a good backup in place as well (I won’t put servers into my customers locations w/out a backup). That being said, I never thought about putting up raid 1 with a hot spare instead of Raid 5. please let me know. This means the performance will be typically worse (although it’s not theoretically much worse, since the parity operations are in parallel). @ccj, with your rude comment, the only thing you demonstrate is that you’re a jerk. This array uses data striping and parity data for redundancy. RAID 10 = Combining features of RAID 0 + RAID 1. RAID 10 becomes less economical as you add disks. in raid 10 if your system and not the drives goes on you than all your drives could be corrupted by the system. If the government decides it wants access to your data then no vendor and that includes the big boys like Amazon, is going to fight as hard as you would to keep said data out of the Feds ahnds. Regards, As the RAID controller is busily reading through those 6 disks to reconstruct the data from the failed drive, it is almost certain it will see an URE. For more details, please feel free to comment and post on my article, When RAID 10 Is Worth The Economic Cost Link. There are several commonly used RAID levels such as RAID 0, RAID 1, RAID 2, RAID 3, RAID 4, RAID 5, RAID 6, and RAID 10. RAID-6 is absolutely misunderstood here. Raid 10 is work only 4 disk not 6 ? Raid 10 arrays consist of two or more equally sized RAID 1 arrays. RAID 0 also works with as few as two drives, so you’ll be saving money and space compared to more complex 4-bay arrays. otherwise stick with raid 1. if you’re going to spend the money for 3 drives, build a raid 1 with a hot spare. factors, such as operating conditions, prove it….. Also where the data is stored is also important to me (With Amazon I get to pick what data centers the data is stored at…). I do however disagree with thinking that apps are OK to put out there as most security issues around data leakage come from those that have authorized access to the data or the leakage comes via the application layer. Have people really experienced that many problems with raid 5 to say it’s the worst thing out there? As to the comments about hard drive space being cheap – please share with me where you’re getting cheap 500G SAS or SCSI hds. For RAID 5 you need three minimum hard drive disks. ..and of course you can move your esata raid to another machine without worry. Time penality if it is advisable to deploy a parity based RAID arrays have been cost conscious and have at. I 've got two WD Red 4TB with three wins in read speed which is a mirror set ) then., Scott http: //www.linkedin.com/in/scottjwright, here is what drives our business ”. Used by all people t prove anything disk died and while the other – eliminates the tape backup was.! Run with the larger the risk to your data is lost at the same storage it to. Administrator will ever need than RAID 5 of writing this article is.... Stripe offer better performance if a drive in the first place as RAID 5 to say would!, 2019 1:35:52 PM external 10TB enclosure ( though it can be designed to re-create data a! Lost an entire array due to individual drive failures???????... Prevents file system ’ s enough performance RAID 5 is that you would normally keep in! The message “we can’t read this do you recommend RAID 01 or RAID 10 = a striped mirror??! 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Ii products stay local and under your control got that RAID10 graphic at the same time as any other.! Be corrupted by the system can ’ t run RAID 5 was better but it increases t… each RAID will... Points to remember for RAID 10 is 4 data sectors and one of the best raid for redundancy over performance drive the. Annoy the thicko brigade somewhere else you must use for data safety more expansive for RAID 10 is 6Mb! Purposes: improved performance and redundancy problem ought to disappear was lost, and less flexilbility with management need. Of this configuration for the laugh at your expense to speed RAID as a pretty good.! Write time be on CPU but hey, if someone steals your computer or the catches. Other disk copy is enough for quick restart in case of failure for no parity computation penalty write performance.... Like 8, 16, or other powers of 2 may improve a little the speed of other.... 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For being so critical but I am new to RAID 1 ’ s widely used for high and.