Need advice with RAID and volumes configuration

[Emil3D]

I have 4 SATA hard drives 2 x 640GB, and 2 x 1.5TB. I'm using this mobo which is with the Intel ICH9R SATA controller. I also have one more internal 250GB PATA hard drive using different controller JMicron. I also have a bunch of other ATA hard drives hanging around with no space in the computer for them.

Currently the 2 x 1.5TB drives are empty and free for any configuration but the 2 x 640GB drives are used as RAID0 and I have Vista installed on them. I'm upgrading to Windows 7 and planning to move Vista to the PATA hard drive by using Norton Ghost and hopefully be able to boot from there. I will use Vista temporarily during the transition period for comparison purposes and things like transferring user and application settings.
I will use mainly Windows 7 but I also want to install Windows XP and be able to boot from it too. I will use Windows XP only occasionally because I have some legacy hard and software that works properly only with XP. I'm planing to install XP after I no longer need Vista and use the internal PATA for a drive with XP on it.
I want a RAID configuration that can provide drive failure protection and also be as fast as possible. The bootable volumes cannot be larger than 2 TB since AFAIK my mobo doesn't support that.

Any ideas will be greatly appreciated.

 

[adampower]

Get a cheap SSD boot disk like the Kingston SSD now V 30gb or even a 40GB intel. Leave your 640's in RAID 0 and RAID 1 your 1.5tb's. Make a nice image of your clean win7 SSD setup on the RAID 1 in case the SSD fails.

Use Win7 Ultimate as it has an XP embedded system. I haven't used it but apparently you can run XP in a window and any xp software will run there as if the machine had booted into xp.

 

[pat]

Leave your 640's in RAID 0 and RAID 1 your 1.5tb's.

I would not waste a full 1.5 drive in a RAID 1 array. I would rather use a software synchronization tool, like PureSync and mirror only important folder rather than the full HDD.

 

[Emil3D]

Thanks for the tips folks,
SSD is very expensive comparing SATA and I will need more than 100GB to make sure that the system and all programs will fit and be able to grow if needed.
I don't mind "wasting" half of the space on my hard drives if that will provide drive failure protection.
I still wonder what RAID configurations are possible with my hard drives and will appreciate any suggestions.

 

[Emil3D]

I have more questions.

1. I would like to test how managing a RAID disk failure works. If I set up and try different RAID configurations for testing purposes and unplug one of the hard drives will this recreate disk failure scenario?

2. I don't know how rebuilding of a RAID with a failed disk works. Do I have to have another set of the same number of identical hard drives or I can copy the data on any hard drive with enough space?

3. Also if the RAID requires identical disks and one fails at a time where such disk cannot be found on the market does that mean the remaining disks cannot be used for such RAID again?

4. Which RAID configurations are possible with 4 disks that are 2 different size pairs, for example can I make RAID 10?

 

[gtvr]

RAID 10 will give you a great combo of speed & redundancy.

1) I'd do that with the PC off, but yes unplugging 1 drive will simulate a failure. With raid 0, there is no rebuilding though.
2) look at the documentation for your system. If 1 drive fails, you will need a spare with at least that much capacity. If the array is still up, you can copy the data off there to another HD with enough space, but that's not a rebuild.
3) They don't have to be identical, although I'd do it that way myself.
4) yes. Never done it, but you should be able to mirror A&B (640s), mirror C&D (1.5tbs) then put those into a raid 0 (this is the effect, you don't do separate steps).

 

[adampower]

You could do a RAID 10 but a traditional RAID 10 with 2 640s and 2 1,500s will give you 1280 gb available (as though you used 4 640s). I would rather 'waste' 1.5tb and have a 1280 gb raid 0 and a 1.5tb raid 1. As to the ssd boot disk you can use a 30gb boot disk and put all of your other programs and such on on or both of the raid partitions. The ssd I bought was on sale for $70. Try booting from the PATA and compare that to any ssd. Not to mention wake from sleep, etc. It takes very little time for the ssd to 'spin up' as it doesn't need to spin. Games and such are basically read intensive and would do well on an HDD. If you do alot of video editing the RAID 0 will serve you well. Anything important can be saved to the RAID 1.

Rebuilding a RAID 1 is easy. Take out failed drive, replace with new drive, allow it to format and 'rebuild'. This is the safest RAID level and always will be. Go ahead and try it by pulling a disk. This is how they test NAS devices and such during benchmarking.

Try this simple Raid Calculator. At the end of the day any RAID you have available to you will require ALL drives in the raid to be the same size. Otherwise it will size everything as though all disks are the same as the smallest.

http://www.ibeast.com/content/tools/RaidCalc/RaidCalc.asp

 

[Emil3D]

Thanks for the input folks, very informative!

So, if I make RAID 10 with 2x640GB and 2x1.5TB and get the array as 1280GB what happens to the remaining space on the two 1.5s? Can I still use it in some way?

 

[Emil3D]

Oh, by the way I see on the wiki page that 10 is 1+0 but they also say that there is 0+1 as if it is different. And on that RAID calculator page they listed the option as 0 +1. All I understand is that the order of the numbers means what takes place first but I have no idea how this matters and if it is something I should know about.

 

[adampower]

Sure, there's raid 10 where you build two separate raid 1 arrays and stripe them. Or, you can take two striped arrays and mirror them (0+1). The difference in a 4 drive array is negligible. If you had an 8 drive array I would recommend 10 over 0+1. But then I would recommend z-raid...

 

[Emil3D]

Thanks,
I still wonder if it is possible to use and how the remaining space of larger pair of disks in RAID10.

As for 10 or 01, I understand how it works but I wonder what's the difference even if its negligible. I guess these options exist because both have advantages and disadvantages in certain cases.

 

[pat]

Puresynce does almost the same as a RAID 1 array but much more simple. Let say you have a folder named "picture" on one 1.5tb drive. You can then create an exact mirror of the "picture" folder and hide it on the second 1.5 tb. So, even if one 1.5 tb fail, you still have a mirror to recover. What puresync allow that RAID 1 don't is that if you want to mirror folder of the RAID 0 array, then you can have puresync to create a mirror where you want it.

RAID 1 SHOULD NOT, nor puresync, be used as backup solution. Because if you mess with one folder, the mirror will be messed too. Another solution would be to use one 1.5 tb in an external eSATA case and use puresync to create backup on that external device when you turn it on.

I have one RAID 0 array and 4 other HDD in my computer with important and not so important stuff and Puresync is much more flexible than a RAID 1 solution.

 

[Emil3D]

Thanks for the suggestion pat, I already have a similar program 'dsynchronize' and it work fine - the way you described. But I do a lot of files management - I constantly move, organize, and reorganize files and folders all the time and keeping track of everything in sync becomes quite involved and also prone to user errors. I also want a constant system backup including program settings and user preferences which is hard to manage on user level. I will continue to use backup and archiving but I need another layer of protection with RAID redundancy.

 

[adampower]

I like Pat's soft solutions. Live backup idea. But you've explored this.

It seems RAID 1 is right for you. Or buy two more 1.5s and RAID 10 an almost 3tb partition.

Have you considered a NAS? I put one together. My latest toy. I love the idea of moving files from my desktop SSD to my NAS at more than 100MB/s. And have the protection of RAID storage and have the flexibility of accessing those files from ANY computer in my house? You can backup the NAS externally for another level of protection. And it gives you a nice, clean, file system to organize. Your files won't be found in program files/users/jimmy/documents/video/oops i meant/desktop/jimmy/doc/friendsandfamily/ or maybe it was desktop/c:/root? or was that just a shortcut to d:?

You can build a simple little box, put your 2 1.5tb disks in it for now. Or add 1 more 1.5tb disk and zraid them. (like raid 5 only better).

Just a thought...

 

[Emil3D]

Thanks adampower, I didn't know about NAS and had to read about. It seems that its major advantage is network usage which is great but for now I'll be using mainly one computer.