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supersi
08-07-2010, 12:34 PM
I have a couple of RAID questions.

My setup is... Asus P5N32-E SLI motherboard (supports RAID 0,1 & 5),
2 x Seagate Barracuda 320GB SATA II hard drives (identical)
Intel Quad CPU Q6600 2.40GHz,
Memory - 4096 MB (4 x 1024 DDR2-SDRAM )


I have tuned, defragged and backed-up my single disk OS (currently using 1 x 320GB Seagate Drive)to an image on an external hard drive using Acronis True Image.

Once i RAID the two 320GB drives (0 or 1, I have not decided yet), can I reinstall the image I've taken across the RAIDed drives?

Can anyone recommend a good 'how to' site for RAIDing?

Deimos
08-07-2010, 03:33 PM
If you are using the built in Intel RAID it will work just fine, however I have noticed that doing it this way causes slower than expected performance, no matter what I did I could not seem to attain the expected perfomance without doing a fresh install of Windows (RAID 0).
I think it has something to do with the Allocation unit size, even though you have the exact same setting on the new install for some reason it runs faster, it may have something to do with the offset of the partition, I'm just guessing though.

supersi
08-07-2010, 03:49 PM
Can I preset the allocation size when I set up the disks?

Nomad
08-07-2010, 04:00 PM
Basically you don't need to prepare the HDDs .. cos if you wanna go the hardware route - with the motherboard it wipes your HDDs I think.

Connect your two HDDs up.
Go into BIOS and change the start up to RAID and maybe the boot sequence.
Restart PC.
Upon boot up, a Raid manager will load up telling you to press CTRL-I I think.
Press it.
Thru that it will ask you what you wanna do.
Restart again.
Put Windows CD in and run setup. You will be asked to provide drivers - this has to be done before hand by downloading off the ASUS website.
Windows installs etc ..


PS. yes I think you have the option under the raid manager to set the allocation size BUT in my experience Windows set up could not continue. My way was to alocate sizes thru Windows setup.

Nomad
08-07-2010, 04:01 PM
If you have RAID and got a image file. Yes you can reload it back on. But maybe not if the image was created using non-RAID to be put back onto a system with RAID.

PS again - when you are registering the HDDs for raid in the manager - provide a meaningful name. Because with a RAID, windows will not tell you whether you have a Seagate or Western Digital. All Windows will say is whatever that name is. If you left it as the default VOLUME01, that will what Windows call it when you look at your hard drive hardware properties.

supersi
08-07-2010, 04:07 PM
Cool, thanks for that. Any idea of the ideal allocation size? and once I've reinstalled Windows would I be able to install my old backup image over the top?

Nomad
08-07-2010, 04:17 PM
Size, dunno, 80GB for the system drive works for me.
I don't think you can use a non-RAID backup file into a RAID setup. B/c it lacks drivers.

If you have RAID already done, you make a image - cool should be sweet.

Deimos
08-07-2010, 05:08 PM
PS. yes I think you have the option under the raid manager to set the allocation size BUT in my experience Windows set up could not continue. My way was to alocate sizes thru Windows setup.

No, RAID controllers do not normally allow you to set the allocation size, this is done by the OS only as it is part of the file system.

RAID allows you to set a stripe size, generally for the intel RAID controllers the default setting is optimal.

Also, Windows default Allocation size is fine for general use, you can gain performance by increasing it (supposedly) but you loose a lot of storage space when you have a lot of small files, e.g. if you have a 1KB file with a file allocation size of 4KB (the default), 3KB is wasted space, if you increase your allocation size to 16KB then you will have 15KB of wasted space for every 1KB file you have (this can have a major influence on disk space of you have a database with a lot of small files).

It makes little difference for large files though.

Deimos
08-07-2010, 05:10 PM
I don't think you can use a non-RAID backup file into a RAID setup. B/c it lacks drivers.

Also wrong.
If he is using the built in Intel RAID it will work perfectly because the drivers are exactly the same for RAID and non-RAID configurations, but as I mentioned before, using a backup to restore the OS on to a RAID array will be detrimental to performance.

Deimos
08-07-2010, 05:12 PM
would I be able to install my old backup image over the top?

The ideal way would be to backup the files you want to keep (documents music settings etc) install your OS from scratch, install your apps, then copy the files back.

supersi
08-07-2010, 10:20 PM
Thank you all. RAID is set up and running. I'll try and restore my backups, I'll try and figure out if the performance get's degraded.