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Nomad
18-03-2010, 07:38 PM
Hi, please advise which option is better :)

Current:
2 500GB HDDs. As diff HDDs.

1a: 1st HDD, 1st partition - OS and s/w.
1b: 1st HDD, 2nd partition, backup of 2nd HDD (below).
1c: 1st HDD, 3rd partition, mucking around, network shared drive.

2: 2nd HDD, not partitioned out. I have GBs of photographs. I use Photoshop and Photoshop Lightroom etc etc .. dSLR RAW files as well as scanned film TIF files - 35mm format sizes and larger formats. 50MB or 100MB sizes or greater for larger formats.

I use SyncBack to sync "2" to "1b". I also sync selected files from"1a" to "2".


Proposing:
RAID off the motherboard - stripe mode. AFAIK, this would be throwing all my files together.

I have a spare 500GB which can be used to sync selected files (treated as a individual HDD) or I can employ RAID 5.


Thanks for your help.
Cheers

pkm
18-03-2010, 08:29 PM
RAID isnt a backup.

Ive head a few horror stories about things not being as simple as they should when repairing a RAID array eg different controller or slightly different drive = no recovery.

I may be wrong, but I would think that using the third 500gb as a yet a another copy of things every so often would be a good idea-and unplugging it when not in use.
Just make sure that the backup is LOGGED so you can be sure it actually worked. If it simply involves checking to see if this months photos are there thats nic and simple-its more tricky if it involves the same files changing.


My personal experience with RAID5

I had a server running RAID5 at home, it ran perfect for over a year (actually, close to two). One night after I went to bed, a drive failed. 3 minutes later another failed. This was a 2 terabyte RAID array.

I came down in the morning to my worst nightmare. Every bit of ‘valuable data’ I had in the world was now gone.

http://blogs.zdnet.com/storage/?p=483
http://fearthecowboy.com/post/Windows-Home-Servers-Drive-Extender-vs-RAID.aspx

nofam
18-03-2010, 08:44 PM
Hi, please advise which option is better :)

Current:
2 500GB HDDs. As diff HDDs.

1a: 1st HDD, 1st partition - OS and s/w.
1b: 1st HDD, 2nd partition, backup of 2nd HDD (below).
1c: 1st HDD, 3rd partition, mucking around, network shared drive.

2: 2nd HDD, not partitioned out. I have GBs of photographs. I use Photoshop and Photoshop Lightroom etc etc .. dSLR RAW files as well as scanned film TIF files - 35mm format sizes and larger formats. 50MB or 100MB sizes or greater for larger formats.

I use SyncBack to sync "2" to "1b". I also sync selected files from"1a" to "2".


Proposing:
RAID off the motherboard - stripe mode. AFAIK, this would be throwing all my files together.

I have a spare 500GB which can be used to sync selected files (treated as a individual HDD) or I can employ RAID 5.


Thanks for your help.
Cheers

How's your budget? :)

Drive 1 - O/S and Apps
Drive 2 - Pictures/photo's/data, plus a backup image of Drive 1 (and incremental backups if you have room)

Really though, if you're doing Photoshop with big RAW files, you should have a third drive as a scratch drive - preferably a VelociRaptor. And a crapload of RAM too. And a Core i7 etc etc. . . .depends how serious you wanna get.

Paul.Cov
19-03-2010, 06:28 AM
I'm very green regarding RAID, but as I understand it, your plan would require drives of exactly the same size, so you won't be able to image a 500GB drive onto a drive or partition of less than 500GB. In some ways, the plan seems a step backwards, although a tad more automated for you.

Problem with a RAID is that if you make a mistake when saving data, then your backup is immediately mucked up as well.
Example... if editting a document and hitting save, instead of renaming the file with Save As...
You've lost your original document entirely on both drives with a RAID when you do this (and it's far too easy to do)
RAID is unforgiving on user error. It's only advantage is in the event of hardware error.

SolMiester
19-03-2010, 07:51 AM
Why does everybody assume a poster wants to use raid as a backup system on here...not once did the OP mention backup..

Nomad
19-03-2010, 08:06 AM
I am happy with my speed. I thought that since I have RAID support why not utilise it. I have a total of 3x Seagate 500GB - SATA2.

Ok, maybe not RAID 5 then.
How about a RAID stripe mode by lumping all my files together and having the 3rd HD as a standalone drive for software syncing in case the 2 drives fail.

Don't want to spend much money, it's just a computer. Not that I don't have funds but a willingness to do.

Would the performance be there despite lumping all files together into a RAID stripe mode over my standard setup?

I use a bit of Photoshop but not huge amount, I am more into digital enhancement than manipulation. That means dust removals, curves adjustments (film), then I just throw it into Lightroom, not sure if LR use a scratch disk, digital I just use LR.

Correction. Currently I sync "2" to "1b" (photos) and I sync "1a" to "2" (My Documents). So I have a copy regardless which drive goes down. Yes I also have a Acronis HDD image of my "1" stored in "1c" and "2".

Cheers.

pkm
19-03-2010, 09:18 AM
Why does everybody assume a poster wants to use raid as a backup system on here...not once did the OP mention backup..

Because 90% of people asking about raid dont realise it isnt a backup. It would be irresponsible to not mention this.

Those that dont ask - already know.

From what I know operations like you are doing are CPU limited not hard drive bandwidth limited - unless you are doing a gigapixel image.

nofam
19-03-2010, 09:39 AM
Because 90% of people asking about raid dont realise it isnt a backup. It would be irresponsible to not mention this.


It would also be irresponsible to not try and talk people out of striping disks when there's no appreciable benefit in most applications, near-double the risk of losing data due to drive failure (striping should actually be called AID 0, because there's no redundancy), and better alternatives for speeding up I/O such as SSD's.

SolMiester
19-03-2010, 10:16 AM
I am happy with my speed. I thought that since I have RAID support why not utilise it. I have a total of 3x Seagate 500GB - SATA2.

Ok, maybe not RAID 5 then.
How about a RAID stripe mode by lumping all my files together and having the 3rd HD as a standalone drive for software syncing in case the 2 drives fail.

Don't want to spend much money, it's just a computer. Not that I don't have funds but a willingness to do.

Would the performance be there despite lumping all files together into a RAID stripe mode over my standard setup?

I use a bit of Photoshop but not huge amount, I am more into digital enhancement than manipulation. That means dust removals, curves adjustments (film), then I just throw it into Lightroom, not sure if LR use a scratch disk, digital I just use LR.

Correction. Currently I sync "2" to "1b" (photos) and I sync "1a" to "2" (My Documents). So I have a copy regardless which drive goes down. Yes I also have a Acronis HDD image of my "1" stored in "1c" and "2".

Cheers.

RIAD 5 is for fault tolerance with the loss of 1 disk to parity...usually used for DATA, not system drives. RAID 5 will give a performance hit as the CPU\Raid Controller and to calc the parity to the 3rd drive...

SolMiester
19-03-2010, 10:17 AM
Because 90% of people asking about raid dont realise it isnt a backup. It would be irresponsible to not mention this.

Those that dont ask - already know.

From what I know operations like you are doing are CPU limited not hard drive bandwidth limited - unless you are doing a gigapixel image.

Therefore, as the OP didn't ask, he already knew?

pkm
19-03-2010, 02:24 PM
Therefore, as the OP didn't ask, he already knew?

It made sense at the time I tell you.:rolleyes:


I dont care, I tell people anyway.

Thebananamonkey
19-03-2010, 07:06 PM
I had a RAID 0 rig for about a year... then a HDD died.

Basically, I lost everything. Didn't matter so much then, but it would be fairly disastrous now.

I'd go for a RAID 1 with your important docs and use the third for your OS. I know this isn't what you were asking, but the performance gain you get from RAID 0 isn't much to write home about.

I'm thinking of getting a 128GB SSD though, just to keep my OS and Steam on. Probably won't happen (car just got cash hungry), but it's something that can speed your comp up big time.

Sweep
19-03-2010, 07:18 PM
I could do a RAID array but why would I?

The speed advantage is not noticable.

Thebananamonkey
19-03-2010, 08:59 PM
Not speed. Redundancy.

For me, data is the most important thing. If I lose an OS then I can always reinstall.
RAID1 on your data would mean you've got some security there.

Sweep
19-03-2010, 10:47 PM
Not speed. Redundancy.

For me, data is the most important thing. If I lose an OS then I can always reinstall.
RAID1 on your data would mean you've got some security there.

Data is important to me too which is why I use images of hard drives. I have the O/S and programs tweaked the way I want.

Billy T
19-03-2010, 11:24 PM
I'm very green regarding RAID, but as I understand it, your plan would require drives of exactly the same size, so you won't be able to image a 500GB drive onto a drive or partition of less than 500GB. In some ways, the plan seems a step backwards, although a tad more automated for you.

As mentioned previously by others, RAID is not a backup strategy, depending on which version you choose, it is for protecting your data in the event of an HDD failure (RAID 1)

You can image a 500GB drive to a much smaller drive or partition because you are only storing an image of the data, not a sector by sector copy of the whole disk.

I have in the past successfully used imaging on previous computers using Norton Ghost and on a couple of occasions restored the C drive with 100% success. My data has always been on a second drive.

Cheers

Billy 8-{)