Everything you need to know about RAID

[Hdesftg]

RAID 0 - RAID 0 is for the people who want the best performance and are willing to sacrifice drive safety in order to implement it.This version of RAID takes your drives and puts them in a single volume, instead of having two 1.5 TB drives, you get one 3 TB volume.  This sounds like it wouldn’t do anything until you realize that this sounds similar to dual channel memory.  Instead of putting in and taking what you are doing out of a single drive, it takes half of each and puts it in or takes it out of both drives.  While this does not always double the performance, it will make it much faster and for people who just want the fastest storage, it could be worth it.  In order to implement RAID 0, you must have at least two drives.  The main downside of this form of RAID is that if one drive fails, both fail, with no way to recover that data because there is no redundancy.  Because of this, it is not advisable to to use this on the drive that your operating system is on.

RAID 1 - This nearly the opposite of RAID 0.  It is for the people that need their data at all costs and are willing to sacrifice half of their total storage for it, although it does not change read or write speed in any dramatic way, it does make write speeds slower.  RAID 1 needs at least two drives in order to be implemented.  It takes your data and duplicates one drive, onto another one; this makes it to where you cannot use that drive for anything except redundancy.  This makes it to where if one drive fails, there is always a back up that the drive can be rebuilt off of.

RAID 5 - This is the version of RAID that most people would benefit from the most.  It takes the data and splits part of it across each of the three or more disks that is needed, while also repeating parts of data across all drives.  This means that not much total storage is lost, and it increases performance, although not as much as RAID 0.  RAID 5 is the most common version of RAID because it has a good balance of safety and speed.  Even if one drive fails, it can be rebuilt;  the only danger in this is that if another drive breaks while this is happening, all storage is lost.

RAID 10 - This is a combination of RAID 1 and RAID 0, hence the name RAID 10.  It takes your data and repeats it across all disks, and takes data out of multiple disks at once as well, but since it has to put the same data across all disks, right performance is decreased and the total storage available is cut in half due to the mirroring of data.  With that being said, it is very fault tolerant and is one of the safer forms of RAID.  The minimum number of disks needed in order to have it is 4 so it is going to be pretty expensive, but for some people it would be the right option to use. 
 

[Helpful Tech Witch]

Do the drives have to be the same size? I have a 1tb and a 500gb is my system right now, and am interested in raid 0.

[dalekphalm]

4 minutes ago, Hdesftg said:

RAID 0 - RAID 0 is for the people who want the best performance and are willing to sacrifice drive safety in order to implement it.This version of RAID takes your drives and puts them in a single volume, instead of having two 1.5 TB drives, you get one 3 TB volume.  This sounds like it wouldn’t do anything until you realize that this sounds similar to dual channel memory.  Instead of putting in and taking what you are doing out of a single drive, it takes half of each and puts it in or takes it out of both drives.  While this does not always double the performance, it will make it much faster and for people who just want the fastest storage, it could be worth it.  In order to implement RAID 0, you must have at least two drives.  The main downside of this form of RAID is that if one drive fails, both fail, with no way to recover that data because there is no redundancy.  Because of this, it is not advisable to to use this on the drive that your operating system is on.

RAID 1 - This nearly the opposite of RAID 0.  It is for the people that need their data at all costs and are willing to sacrifice half of their total storage for it, although it does not change read or write speed in any dramatic way, it does make write speeds slower.  RAID 1 needs at least two drives in order to be implemented.  It takes your data and duplicates one drive, onto another one; this makes it to where you cannot use that drive for anything except redundancy.  This makes it to where if one drive fails, there is always a back up that the drive can be rebuilt off of.

RAID 5 - This is the version of RAID that most people would benefit from the most.  It takes the data and splits part of it across each of the three or more disks that is needed, while also repeating parts of data across all drives.  This means that not much total storage is lost, and it increases performance, although not as much as RAID 0.  RAID 5 is the most common version of RAID because it has a good balance of safety and speed.  Even if one drive fails, it can be rebuilt;  the only danger in this is that if another drive breaks while this is happening, all storage is lost.

RAID 10 - This is a combination of RAID 1 and RAID 0, hence the name RAID 10.  It takes your data and repeats it across all disks, and takes data out of multiple disks at once as well, but since it has to put the same data across all disks, right performance is decreased and the total storage available is cut in half due to the mirroring of data.  With that being said, it is very fault tolerant and is one of the safer forms of RAID.  The minimum number of disks needed in order to have it is 4 so it is going to be pretty expensive, but for some people it would be the right option to use. 
 

Welcome to the forums!

 

I appreciate your enthusiasm, but I'm going to give you some advice:

No one is going to read that. You literally posted a single wall of test, with little to no formatting.

 

If you'd like to create a helpful guide that breaks down and explains RAID, that's an awesome idea. But you need to break that wall down into sections, with titles/headers, so that people will want to read past the first line.

 

Also, you didn't even talk about RAID6, which is extremely important since due to drive sizes and average uncorrectable error rates in modern large HDD's, RAID5 can become dangerous to use after a certain point (the issue is that statistically, you run a high chance of running into an error during a rebuild, which will essentially kill the array and make the data unrecoverable).

[Helpful Tech Witch]

3 minutes ago, dalekphalm said:

-snip snipidy snip snip-

True. Probably the guides subfor would be a better fit for this.

[dalekphalm]

1 minute ago, HelpfulTechWizard said:

True. Probably the guides subfor would be a better fit for this.

Yes that would be a good place, but having it here isn't a problem (though frankly without it being pinned, it'll simply get buried sooner or later).

 

If the guide was fleshed out more, with better details and some of the other RAID levels (RAID6 particularly - maybe cover RAID50/60 too), and with much better formatting, it might get pinned if useful enough.

[Electronics Wizardy]

11 minutes ago, HelpfulTechWizard said:

Do the drives have to be the same size? I have a 1tb and a 500gb is my system right now, and am interested in raid 0.

Depends on the implentation, but normally yes, or it will use the capacity of the samller drive.

 

For that usecase, Id keep them seprate.

[Hdesftg]

11 minutes ago, HelpfulTechWizard said:

Do the drives have to be the same size? I have a 1tb and a 500gb is my system right now, and am interested in raid 0.

Not technically.  I would recommend it though as if you did create the array with the two different drive sizes then there will only be the space of the smaller drive.  This is only if they are the same model drives though.  If they are two completely drives then they will not work at all as far as I know.

[Helpful Tech Witch]

Just now, Hdesftg said:

Not technically.  I would recommend it though as if you did create the array with the two different drive sizes then there will only be the space of the smaller drive.  This is only if they are the same model drives though.  If they are two completely drives then they will not work at all as far as I know.

All of the HDDs I have are WD models with almost the same design. But thanks for the info. Literally, I have drives from the birth of data, to a 1 year old 1tb one. 

[dalekphalm]

1 minute ago, Electronics Wizardy said:

Depends on the implentation, but normally yes, or it will use the capacity of the samller drive.

 

For that usecase, Id keep them seprate.

To expand upon this, most Hardware RAID cards will let you use drives of different sizes, but it'll treat all drives in the RAID array as if they were the same size as the smallest drive.

 

So a 1TB + 500GB in RAID0 = 1TB usable space. This means you do get a slight performance boost over a single drive (though hardly, with only 2 mech drives in RAID0), but you don't gain any space at all.

 

You can also run into issues with differing performance characteristics of drives of different sizes - the array will be limited by the slowest drive.

 

In that case, I'd frankly just use them separately. If you need a larger drive, sell the 2 you have and buy a 2TB HDD. If you need something faster, add an SSD (either full blown, or as a cache type system), or any number of other options.