What RAID array to choose for your dedicated server
RAID arrays are something worth mentioning when you think about the protection of your data from any loss. That’s why this article might be useful for you. Choosing a suitable RAID array may be beneficial to you because not only it can save your precious data but save some budget that you can spend on something more important. Anyway, what is RAID?
RAID is an acronym for Redundant Array of Independent Disks. Invented in 1987 by David Patterson, Garth A. Gibson, and Randy Katz it is quickly has become a convenient way for companies to store their data without worrying that it might go corrupt. Basically, it increases the redundancy and fault tolerance of the HDDs or SSDs by combining them via specific hardware or software in such a way that the data is written simultaneously on each hard drive. So even if one fails the other one will work as usual having files at your disposal. Of course, during its 30 years of history, there were numerous kinds of RAIDs created. Let’s check them out to see what RAID is suitable for you.
Hardware vs. Software RAID
In terms of budget, there are two types of RAID: Hardware and Software. More expensive and redundant and cheaper but gives you less redundancy.
If we talk about the Software option it’s just a specific software that controls specific procedures in RAID and does all the work there. Plus you utilize some of the server resources for software to work, the more load on the storage the bigger is the load on the server. For usual tasks, it might be enough. For example, if it is a home PC, but for complex tasks and it is advised to switch to hardware RAID from the very beginning.
Hardware RAID has a specific hardware controller which controls all the processes. It does not consume any resources from the server and can work on its own. The disadvantage is the cost of course. Software is free while the controller costs money. Every controller has an inbuilt battery which helps to save the data in case of a power outage.
Now that we have finished with the difference between software and hardware let’s proceed with types of RAIDs then.
The first RAID was initially invented in order to increase the read/writing speed of the slow HDDs. It utilizes the process of disk stripping to read/write data from multiple storage drives and combine it into one. This allows you to double the speed but you are stripping yourself from redundancy. Imagine that you have two 2TB disks with read/write speed of 200 and 150mbs. If you combine them in RAID0 you will receive 1 disk with 4TB and read/write speed of 400 and 300mbs. Sounds cool, right? Yet if one of the disks fails you will lose all of your data. Because your files are scattered all across those disks and it is very difficult to retrieve them back. Not recommended for critical projects.
Did you want redundancy? You can achieve it with RAID1. Built with a principle of mirroring it can have data available even if one of the disks fails. Probably the most popular way of cheap hardware redundancy you can achieve, using only 2 disks at the same time. Well, basically you can build RAID1 even with 4 or 6 disks at the same time. Just remember that they should be the same. Building an array with 1TB HDD and 2TB HDD is not possible. Let’s talk about the downsides. First, your read/writing speed will not increase but stay the same. Second, you need will receive your cumulative space split in half. So 1TB plus 1TB equals not 2TB but 1TB. If your project requires your data to be protected but doesn’t require too much read-write speed, then RAID1 is a choice for you.
RAID 10 is an ultimate combination of RAID0 and RAID1 which allows you to have an increased storage size and improved read and writing speeds. Redundancy is achieved through mirroring. The downside of this array is the expense of the setup. It works only with 4 disks of the same size. So basically 4TB+4TB+4TB+4TB means you receive 8TB but with all advantages that RAID 1 and 0 can provide to you. It is the most fault-tolerant solution because the whole RAID can fail only if the 3 out of 4 hard drives go corrupt.
A great choice for those who require the same from both worlds of RAID 1 and 0, yet don’t want to buy extra hard drives. RAID5 requires at least 3 hard drives to operate. Because the 3rd control drive is used for parity and it basically controls how the process of data distribution works across all the drives. As for the additional advantages if you want to imitate RAID10 with 4 drives you will lose 50% of the storage but with RAID5 you will lose only 25%. The more drives you will add the more storage you will save in the future. The downside is when at least 1 drive goes down you’ll notice a significant performance hit. Also it is very difficult to restore the data if one of the disks fails, so make sure that you monitor S.M.A.R.T attributes on a constant basis. Should you look for something quite stable yet not so pricey, go for RAID5.
The evolution of the RAID5 where additional parity block has been added. Additional block means additional disk, which means that the minimum set of disks for RAID6 to work is 4.
It was initially developed to protect the system if 2 out of 4 disks will fail immediately. While you receive the same read speed from RAID6, RAID5, or RAID10; RAID6 lacks the writing speed for up to 50% depending on different scenarios. If you value safety over speed then RAID6 is the best option out there. It’s the most redundant array out of all mentioned here. Usually, it is utilized in computing environments that require a high level of continuous data availability. As for the downsides, it is the writing speed, the slowest out of all RAIDs here. So it’s basically MAX at one and MIN at the other.
Should you consider RAID for your server?
RAID offers a vast layer of fault tolerance for your server. It will prevent your data from getting destroyed due to mechanical reasons, but please bear in mind that it will not protect your data from hackers or from any force majeure that can occur, like a fire outbreak in the data center or typhoon, that’s why it is always advisable to have a backup stored somewhere in other data center in the other location, just in case. For additional questions about RAID arrays and the prices for them, make sure to contact the BlueServers team via LiveChat. Take care!