A silly question about RAID 0

[AleksanderK]

So if I buy 2 2tb drives and use RAID 0 to create one 4tb drive that would be faster than just one 4tb drive, what would happen if I had to put the drives into a new system? Will RAID 0 be transferred to the new MOBO and etc. Also, will I lose any data?

[Rohime]

6 minutes ago, AleksanderK said:

So if I buy 2 2tb drives and use RAID 0 to create one 4tb drive that would be faster than just one 4tb drive, what would happen if I had to put the drives into a new system? Will RAID 0 be transferred to the new MOBO and etc. Also, will I lose any data?

1 - yes, faster for READ, but not for WRITE (typically).

2 - if it is software raid you will probably lose all the data unless you are really careful and know exactly what you are doing.   Best to assume you will lose all data.

[AleksanderK]

2 minutes ago, Rohime said:

1 - yes, faster for READ, but not for WRITE (typically).

2 - if it is software raid you will probably lose all the data unless you are really careful and know exactly what you are doing.   Best to assume you will lose all data.

Excuse me, what exactly is "software raid"? Is it when you put the drives in RAID in BIOS?

[DHelios]

When you create a RAID setup, the RAID controller and drives become sort of a unit. The data on each drive will not be readable individually. Other RAID controllers will likely be unable to make sense of the data, even with both drives connected.

 

If you have a separate RAID add-in card, you should be able to transfer the entire setup from one computer to another (but read the RAID card's manual, two times if you have to!). If you're using your motherboard's on-board RAID capabilities, you may be able to transfer just the drives and rebuild the RAID, if your new motherboard uses the same version of the same chipset, with the same firmware.

 

All in all, that's a lot of conditions. So TL;DR: in most cases you will not be able to transfer a RAID setup to another motherboard.

[AleksanderK]

2 minutes ago, DHelios said:

When you create a RAID setup, the RAID controller and drives become sort of a unit. The data on each drive will not be readable individually. Other RAID controllers will likely be unable to make sense of the data, even with both drives connected.

 

If you have a separate RAID add-in card, you should be able to transfer the entire setup from one computer to another (but read the RAID card's manual, two times if you have to!). If you're using your motherboard's on-board RAID capabilities, you may be able to transfer just the drives and rebuild the RAID, if your new motherboard uses the same version of the same chipset, with the same firmware.

 

All in all, that's a lot of conditions. So TL;DR: in most cases you will not be able to transfer a RAID setup to another motherboard.

That's to much "ifs" for me. Probably better off with just one 4tb drive

[DHelios]

15 minutes ago, AleksanderK said:

Excuse me, what exactly is "software raid"? Is it when you put the drives in RAID in BIOS?

Software RAID is when there is no specific RAID hardware. Most motherboard RAID features are on a software level; the drives are linked at a driver- or OS-level. It's cheaper because it does not require additional electronics, but it takes up some of your CPU's power to handle your data, and whilst it's usually faster for read speeds than a single drive, write speeds are often not much better if at all.

 

Hardware RAID uses specific controller chips and the like that take care of all the data. As far as the OS knows, there's only one hardware device (the RAID controller), and since this hardware is specialised for its task it's very efficient. It uses a bit more power and often costs a lot more, but the performance is excellent, often both in read and write speeds.

 

edit:
To answer the second question: Most consumer motherboards use a software RAID solution. After all, hardware RAID costs extra, and any RAID features are used by only a small percentage of consumers.

[DHelios]

4 minutes ago, AleksanderK said:

That's to much "ifs" for me. Probably better off with just one 4tb drive

If you don't really need the read speed improvements, then also keep in mind data security. A 2x2TB RAID0 setup has more than twice the failure rate of a single 4TB drive (assuming the 2TB and 4TB drives used have the same base failure rate). After all, if each drive has a 0.02% chance to fail on any given day, then with a single 4TB drive you have a 0.02% chance to lose all your data today. With the RAID0 setup, you have 0.02% chance for the one drive to fail, 0.02% for the other drive to fail, and then there's a chance for your RAID controller to fail. That's a >0.04% chance to lose all your data today!

 

RAID1 mirrors go the other way around: If you have two drives, there's still a 0.04% that a drive fails today. But if it does, you can replace it and you won't lose your data because it's on both drives. You get to keep working to boot! Of course you can still lose your data if the other drive fails before you replace the broken one. But though either drive has a 0.02% chance to fail on any given day, the chance of those two days being the same day is only 0.0004%!

 

Of course 0.02% is just an example value here, but you get the idea. And since any setup of any kind of drives can fail... Make back-ups of anything important. Please.

[AleksanderK]

2 minutes ago, DHelios said:

If you don't really need the read speed improvements, then also keep in mind data security. A 2x2TB RAID0 setup has more than twice the failure rate of a single 4TB drive (assuming the 2TB and 4TB drives used have the same base failure rate). After all, if each drive has a 0.02% chance to fail on any given day, then with a single 4TB drive you have a 0.02% chance to lose all your data today. With the RAID0 setup, you have 0.02% chance for the one drive to fail, 0.02% for the other drive to fail, and then there's a chance for your RAID controller to fail. That's a >0.04% chance to lose all your data today!

 

RAID1 mirrors go the other way around: If you have two drives, there's still a 0.04% that a drive fails today. But if it does, you can replace it and you won't lose your data because it's on both drives. You get to keep working to boot! Of course you can still lose your data if the other drive fails before you replace the broken one. But though either drive has a 0.02% chance to fail on any given day, the chance of those two days being the same day is only 0.0004%!

 

Of course 0.02% is just an example value here, but you get the idea. And since any setup of any kind of drives can fail... Make back-ups of anything important. Please.

K, thanks

[Rohime]

17 minutes ago, AleksanderK said:

That's to much "ifs" for me. Probably better off with just one 4tb drive

Yes.   Get a 4TB hybrid with SSD embedded cache.

http://www.storagereview.com/wd_blue_sshd_4tb_review 

[AleksanderK]

2 minutes ago, Rohime said:

Yes.   Get a 4TB hybrid with SSD embedded cache.

http://www.storagereview.com/wd_blue_sshd_4tb_review 

Well, I could use RAM cache

[Rohime]

1 minute ago, AleksanderK said:

Well, I could use RAM cache

its a different level of cache.   You could mean RAM drive, but thats a different thing entirely (with its own availability / reliability issues).