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What's the difference between RAID 1 software mirroring and Fake RAID?

What's the difference between RAID 1 software mirroring and Fake RAID?

I've just ordered two new hard drives for my main desktop and a copy of Windows 7 Professional 64-bit. I'd like to do a clean install of Windows 7 onto the new drives (leaving my old Windows XP Professional boot partition around for a while in case something goes disastrously wrong, etc.). I want to have them set up in mirrored (RAID 1) mode.

Asked by: Guest | Views: 339
Total answers/comments: 5
Guest [Entry]

"I think performance wise, your best bet is to try both and benchmark, and share the results here for everyone to see! I would suggest using the ATTO Disk Benchmark utility.

As far as which I'd choose, I hate ""fake raid"". Always caused me more problems than it prevented. Get a real RAID controller or do software RAID. The only reason software RAID wasn't very popular in the past is because of performance issues, but that's a thing of the past."
Guest [Entry]

"Having had my primary IDE controller crash on a running Windows system with Software RAID -- and with my disks on separate controllers -- I'm sold on that being the right choice. When the IDE controller crashed, the visible result was a little triangle warning icon in the System Tray notifying me of the problem, but otherwise the system continued running normally. It was really quite impressive once I realized the magnitude of what had happened.

Compare this to the case with Hardware RAID where, if you lose the controller, you've lost both disks and the system obviously crashes."
Guest [Entry]

"Some small things to consider:

The likelihood of whether you will ever need to run things like disk imaging software: some can't see through a hardware RAID controller when it is enabled.

You just purchased two drives - presumably identical drives - almost sequential serial numbers? If so and there is a problem with the batch, both may fail simultaneously. RAID won't buy you anything under this circumstance. You should buy them seperately - hopefully from different batches.

When RAIDs break, check if you need to be out of the OS to rebuild the mirror. On the software mirrors I have seen, you can boot, run the OS and remirror in the background, but it slows you down (obviously as it is reading good drive and writing to the mirror.) I'm not sure what would be required for this hardware RAID."
Guest [Entry]

"I could help here - I've been on the phone with Microsoft's support people and the Western Digital people. I just purchased two 1 TB drives as I wanted some assurance (due to my backup lazines) that my data would be replicated/backed up with minimal interference. Well... this is what I know:

You can setup mirroring to happen (which is like RAID 1) but not really by doing the following - with a pitfall.

You have to install Windows 7 in order to mirror - so given that you have done that
I typically like to partition off my disk 0 into a C and D where C is for OS stuff and programs and D is for data. Each drive disk 0 and 1 must be set to Dynamic. (DO NOT format disk 1 - leave it unformatted - otherwise the next step will not work).
Right click on drive D from disk 0 and left click on Add Mirror - when you do this you will see disk 1 appear and click on it. The software found disk 1 as it is completely unallocated and see's it as a free drive to mirror on.
Click OK and in a few moments you will see the same drive space allocated for disk 0 drive D on disk 1 and it names it the same - drive D and resynchronising with a percentage showing progress. This can take some time even with no data to synchronise.

When the resynchronising is complete - no further action is needed - except you might have to rescan the drive by left clicking it and choosing Action from the menu then Scan Disks - takes just a moment and you're done.

The ONLY problem is - you can't mirror disk 0 - drive C! I'm so frustrated - it attempts it, but gets only so far and then you get a failure message on the disk 0 area and sometimes you get Virtual Disk Manager Error ""No Extents Were Found For The Plex"". What is the matter with that?! I have tried researching and perhaps not enough but neither Microsoft or Western Digital could help me. They don't know what it means and perhaps Windows 7 is not quite ready yet to take advantage of the driving mirroring capabilities.

How to get around this? - I would really appreciate knowing how you did it! Please email me at freeman.jeffrey@verizon.net.

That's all I got - took me antire day working with Microsoft an Western Digital do get this information."
Guest [Entry]

"Don't do it.

I have just gone through 3 months of drama with a software RAID 5 and Windows 7 (64-bit Premium). When the RAID was working it wasn't that quick. The system kept dropping hard disk drives - 6 in total. The last straw was when 2 hard disk drives were dropped, leaving the system in a very poor state. I have just de-RAIDed the system now and have 3 x 1 TB hard disk drives there (as b4 with the RAID) and the system is no slower and much more reliable."