IT in Three: What is RAID?

Mark Twain once said you could put all of your eggs in one basket you just had to keep an eye on that basket it's important to note that Mark Twain never worked in IT today's topic is raid which stands for redundant array of independent disks or if you're old school inexpensive disks so imagine that this bag of eggs is a file say a Word document and the individual eggs represent the packets of data that make up the file saving directly to a physical Drive would look something like this placing all of those eggs one after another directly into a single basket but what if you ran out of room in your basket or worse yet what if something happened to the basket this is where raid comes in Freight allows you to take a collection of disks and configure them in such a way that your computer recognizes them as one logical disk unit so why do this well perhaps the most important reason is redundancy and if redundancy is a big priority RAID one is a great place to start see with raid 1 you mirror your drives which means that anything that you save on onedrive you save on another just like it so if you end up having a drive failure you've got a spare however there are some downsides first you're having to write to two drives now which can make things a little bit slower but even worse we're now using a total of 2 terabytes of available storage for only one usable terabyte so sure with raid 1 you aren't putting all of your eggs in one basket but you are always carrying twice as many baskets as you're using so what if you decided I don't care about redundancy I want speed and efficient use of drive space this is where raid zero comes in see raid zero stripes data across multiple drives basically what this means is that data is being saved bit by bit across drives which again act as one because much of this data is written almost simultaneously raid zero can provide faster write speeds however it's called raid zero for a reason C raid zero provides no redundancy whatsoever so while you're not putting all of your eggs in one basket you may as well be because if you lose one Drive you no longer have the full data set and this means our word document is now gone forever fortunately there are a few other options available if you'd like to have more usable drive space but would still like to keep data safe from a drive failure and this is where raid 5 comes in so first with raid 5 you'll need at least three drives data is striped across dry like in raid zero but now packets of parity data are created by calculating a combination of the other bits of data being stored this continues with these packets of parity data being placed in different drives sequentially as the data is saved now what's cool about raid 5 is that if any one drive fails you can still recreate all of your data using the parity data so now you're making better use of available disk space and you have redundancy in case of a drive failure so what's the catch well because writing these parity bits take some calculation you're adding complexity which means in case of a drive failure some additional recovery time so at this point we've covered reliable raid 1 speedy raid 0 and well-rounded but complex raid 5 there are other raid levels but we won't cover those here is there much less common however it is useful to know that the raid levels we've discussed can be nested to create new raid solutions remember how we said raid uses an array of drives to create a single logical drive well once you have these logical drives you can use them in a new raid configuration like in raid 1+0 or as it's commonly known raked in let's start by taking two physical drives to create a single logical drive using raid 1 and now another logical raid 1 drive now that we have two logical drives we can again use raid to create an array in the case of raid 10 would use raid 0 so now we have the speed of raid 0 supported by the reliability of mirrored data using raid 1 so as you can see regardless of your needs raid provides a storage solution to keep all of your eggs safe and sound please consult the links at the end of this video before implementing rate side effects of rate include increased redundancy and/or performance raid should not be used as a replacement for regular network backups children should not attempt to implement raid unsupervised some assembly is required be sure to check with the Spiceworks community for details [Music] [Music]

Channel: Spiceworks

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Keywords: raid, what is raid, Spiceworks (Organization), IT in Three, raid 0, raid 1, raid 0+1, raid 10, raid 5, technology, help desk, network monitoring, spiceworks.com

Id: Aa0RTgxJJy8

Length: 4min 22sec (262 seconds)

Published: Mon Dec 02 2013