Raid 0+1

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I know the RAID topic has been beaten to death but I have four WD 500gb blacks and I havent even filled one of them yet. I was doing some research on RAID 0 but am afraid of losing data so now i'm lookingat RAID 0+1. My questions are...

1. If one of the RAID 0 drives fails can I get the data back from the mirrored drives?

2. What do I do if one of the mirrored drives fails?

3. I understand that my storage capacity will no longer be two TB but only 500gb. Is this correct?

4. Is it possible to have a RAID 0 array and just a simple backup? If so, would that be better than the RAID 0+1 array?

5. Does the speed of RAID 0 increase with the number of drives? eg. 3 drives are faster than 2 drives in RAID 0.

Thansk alot for any help you can give me. This stuff makes my brain hurt but I am a performance junkie and also like to have something not everybody else has.
 
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Sorry I can't answer most of your questions right now, but I would go with #4 personally. As long as you don't need your computer to have 100% uptime, and in the event that a drive does fail you don't mind re-installing Windows, it's the best option to have the best performance and maximum drive capacity.

I would setup 4 drives in RAID 0, which would give you 2TB of storage, and since you said you haven't filled up even one yet you could get by with a 500GB external hard drive for backup (although I would go with at least a 1TB now since they aren't much more). One thing people seem to forget is that even though RAID 1 mirrors the drive, it is NOT a backup solution. Files are still susceptible to accidental deletion, viruses, and corruption.
 
I would choose RAID 5.

You lose the capacity of one drive, but if any one drive fails, it can be replaced without losing any data. :good:
 
[-0MEGA-];1403256 said:
Sorry I can't answer most of your questions right now, but I would go with #4 personally. As long as you don't need your computer to have 100% uptime, and in the event that a drive does fail you don't mind re-installing Windows, it's the best option to have the best performance and maximum drive capacity. I dont mind having to re-install windows at all.

I would setup 4 drives in RAID 0, which would give you 2TB of storage, I thought I read somewhere that in a RAID 0 array the capacity is only as big as the smallest drive. and since you said you haven't filled up even one yet you could get by with a 500GB external hard drive for backup (although I would go with at least a 1TB now since they aren't much more). One thing people seem to forget is that even though RAID 1 mirrors the drive, it is NOT a backup solution. Files are still susceptible to accidental deletion, viruses, and corruption.
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I know it is not the same as a backup but I am only worried about a failing drive. Corruption, accidental deletion, and viruses dont worry me. I have only had one virus screw my pc up since I was a young kid and that was cause I had AVG off for some reason. I dont do anything important on the computer. A little music for the flash drive for my trucks system, web surfing, lots of games, and netflix. If I lose the music it's ok cause it's in the truck. If I lose the games thats ok cause I have the disks. Anything else that I could lose would just make me swear some and then I would get over it.

Bodaggit23 said:
I would choose RAID 5.

You lose the capacity of one drive, but if any one drive fails, it can be replaced without losing any data. :good:
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Is a RAID 5 array faster than a single regular drive? Also when one fails, what do you do, just pop in a new one and pound a few keys and it's okay again? Thanks for your help guys. I really appriciate it.
 
Raid 5 is striping with parity... if 1 fails thats ok. I would use 3 disks in your raid 5.. giving you 1TB of storage and set the 4th up as a online/hot spare. so you could in theory lose 2 drives before you have to start worrying. as far as performance i believe your write speed will improve. and no you dont do anything if you lose a drive it will still work you may however have to go in depending on your raid equipment and software and activate the online spare. but when you replace a drive you will have to go in to the interface and tell it to add that new drive to the array.

http://en.wikipedia.org/wiki/RAID
 
if your mobo supports raid 5 then it wont be using software raid. your mobo has a raid controller... hardware raid.

i wouldnt recommend anything besides 0 or 1 for software raid.
 
I read that page as well as some others before it but sometimes I have trouble making sense of what they are saying. I dont mind having a new WD 500gb on hand in case of a failure. I have space in my case for one at least, that way it is safe and I could just leave it unplugged.
 
you wont need another one you have 4

Disk 1 RAID 5
Disk 2 RAID 5
Disk 3 RAID 5
Disk 4 SPARE

if any one of the disks 1-3 die disk 4 will jump in giving you time to buy a replacement and put it in.

if 2 disks die then 4 will jump in but you will still be down 1 disk and will have to replace it ASAP, your system will still work but you might experience a performance degrade.

if 3 die then your screwed.
 
Well, lets kind of make one thing clear, mirroring drives is not a back up. It is a mirror. A back up is a known good source of data, which you have backed up. Mirroring is an exact replication of what is currently used in your system. If you were to say, contract a virus, it would be mirrored to the other disks in the array immediately, thus you wouldn't have a clean back up.

Now on to the actual need and risk vs reward of running RAID. Of course, as already mentioned RAID 5 is going to be probably the best bet for data throughput increased performance and stability as one drive is basically sacrificed for meta data so if a drive in the array fails there is some record of what data is stored where. Since in an array they (all separate disks) are randomly writing data in synchronicity as if it were only one drive.

RAID 0, for 90% of users will not get that much of a system boost, so why even run it? It won't play movies better, it won't give you more frames per a second in games, it won't make anything in gaming faster actually with the exception of load times, and even that may vary.

Now, if you are going to manipulate large amounts of large files, like video editing, raw digital photo editing, massive graphic arts projects, rendering audio or video, or working with massive amounts of data in like a database or something, a RAID will benefit you for the performance of striping.

Do note that RAID 1 actually lowers performance a bit because of the bottle neck of both drives always being in sync with each other. If one slows down, the other matches the same speed for data integrity.

I always gotta ask people, is RAID really what you want to do? if so, then more power to ya, but if you won't benefit from it, why run it?
 
tlarkin said:
Well, lets kind of make one thing clear, mirroring drives is not a back up. It is a mirror. A back up is a known good source of data, which you have backed up. Mirroring is an exact replication of what is currently used in your system. If you were to say, contract a virus, it would be mirrored to the other disks in the array immediately, thus you wouldn't have a clean back up.

Now on to the actual need and risk vs reward of running RAID. Of course, as already mentioned RAID 5 is going to be probably the best bet for data throughput increased performance and stability as one drive is basically sacrificed for meta data so if a drive in the array fails there is some record of what data is stored where. Since in an array they (all separate disks) are randomly writing data in synchronicity as if it were only one drive.

RAID 0, for 90% of users will not get that much of a system boost, so why even run it? It won't play movies better, it won't give you more frames per a second in games, it won't make anything in gaming faster actually with the exception of load times, and even that may vary.

Now, if you are going to manipulate large amounts of large files, like video editing, raw digital photo editing, massive graphic arts projects, rendering audio or video, or working with massive amounts of data in like a database or something, a RAID will benefit you for the performance of striping.

Do note that RAID 1 actually lowers performance a bit because of the bottle neck of both drives always being in sync with each other. If one slows down, the other matches the same speed for data integrity. I think I am going to go ahead with the RAID 5 array.

I always gotta ask people, is RAID really what you want to do? if so, then more power to ya, but if you won't benefit from it, why run it?
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I dont want you to think I am being a punk or smart cause I am not, but this is why I am a member of this forum and also why I posted this topic. I want to hear from people that know what they are talking about like all of yourselves (is that even a word? It looks wrong.) I just thought it would be cool to have a RAID array cause nobody I know has one and also I thought I would get a boost in perf. All I do is stream netflix watch movies off HDD and DVD/BD drives and lots of gaming. No video or photo editing or databases. This is starting to sound like a stupid idea.
 
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Cams said:
I dont want you to think I am being a punk or smart cause I am not, but this is why I am a member of this forum and also why I posted this topic. I want to hear from people that know what they are talking about like all of yourselves (is that even a word? It looks wrong.) I just thought it would be cool to have a RAID array cause nobody I know has one and also I thought I would get a boost in perf. All I do is stream netflix watch movies off HDD and DVD/BD drives and lots of gaming. No video or photo editing or databases. This is starting to sound like a stupid idea.
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It is your computer you do whatever you want with it. However, running an array like RAID 0 will not boost performance of multimedia play back and gaming. The only thing it may boost in gaming is load times.

Now, if you do insane amounts of multitasking, like you need to open up 50 different office documents at once and you want it to open fairly quickly, RAID will help there. However, what kind of computer user needs that? I guess you got the bragging factor..."Yeah dude my PC can open 50 Microsoft office documents in under 10 seconds, at the same time!"

If you want to run RAID by all means go ahead. I am just pointing out it probably doesn't do exactly what you think it will do. I know people love to brag about their boot times with RAID 0, but I maybe reboot my PC once a week? Maybe once every two weeks?
 
a raid isnt a stupid idea, but we are just trying to make sure its the right solution to your goal. If you want a performance booster maybe get a 10K drive instead of the 7200.

The main 2 things people use raids for is increased space and fault tolerance.
 
The point being missed here is that ALL your applications will load faster with certain RAID arrays.

Sure, certain SSD's (not sure about the one you've chosen) will blow away a RAID 5 array, but the 3 drives I'm going to get will cost about the same as that SSD, and I'll have a snappy 1TB "C:" drive, with data loss protection. :good:
 
Bodaggit23 said:
The point being missed here is that ALL your applications will load faster with certain RAID arrays.

Sure, certain SSD's (not sure about the one you've chosen) will blow away a RAID 5 array, but the 3 drives I'm going to get will cost about the same as that SSD, and I'll have a snappy 1TB "C:" drive, with data loss protection. :good:
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Yes, while true, it is very subjective. Open one office document on a non RAID 0 and one off a RAID 0 and clock it. You won't notice much of a difference or any, because it is such a small amount of data being processed. By open I mean, double click the file and have it launch the app to read the file. Now, when you get into opening lots of files at once, yes definitely a noticeable speed difference.

It is just like benchmarks. Sure, scores can mean certain things on paper but don't always reflect real time actual usage.
 
Bodaggit23 said:
Maybe some people do it just for sake of not losing their data?
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Well redundancy is not really a back up, when referring to RAID 1. I see it as a technology for a production machine that can have zero down time. For example, you are a photographer and one of your computers simply processes digital film all the time constantly and it must be ran pretty much every hour you are open and sometimes it must run 24/7. Every second the machine is down you are losing money on it. So, you put in a RAID 1. Drive 0 fails, RAID 1 can switch over to Drive 1 and you are back in business with very little down time. It is not a back up though, because if data gets corrupted, you contract a virus, or something else bad happens it is mirrored to both drives immediately, so now both drives share the problem. Another caveat is if you delete a file, it is deleted on both drives instantly. Also, if you have something really bad happen like a power surge, lightning strike or both drives fail back to back, you are out of data.

RAID 5, is also about production time, but with the performance boost of drive striping. I really don't see it as an end user solution unless you need your machine to have zero down time.

While, like I said earlier, it is your computer do as you wish with it and run RAID 0,1,5,1+0 if you wish, but I doubt you'll get much actual real world benefit from it unless you are the type of user that needs that technology.

I just think it is more efficient to run one high speed drive (10k or 15k RPM drive with lots and lots of cache) for OS and apps, and then run one large one for data. It is a more simple set up, more simple to maintain and less margin for error. Plus, you put a lot more wear and tear on your hard disks when they are all working together because they are all constantly running.

So, if you think you can benefit from it, then great do it. My personal opinion is most people don't need it, and won't really benefit from it. that of course, is just my opinion.
 
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tlarkin said:
Well redundancy is not really a back up, when referring to RAID 1.
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I didn't say anything about RAID being a substitute for backups, nor did I, or would I choose RAID 1.

I suggested RAID 5, to reduce load times on most if not all applications, and the warm fuzzy feeling that if one of your drives fails, you can replace it without losing anything.

Creating backups does nothing for performance. ;)
 
I know, and I was trying to point out that running RAID 5 for not losing data is not really a good practice. Running RAID 5 for zero down time is a good practice. If two drives fail, which may not be likely but say a small surge comes in or there are manufacturing defects with that drive, then you are out all your data regardless.

RAIDs aren't really meant for preserving data as much as they for keeping the machine running with no down time. That was the point I was trying to make. The not losing data is more a side benefit from the benefit of having redundancy.

I also know you know the difference but was trying to explain it this way for the OP's benefit.
 
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