I currently have a 500GB hard drive as my OS + App drive, and 2x750GB hard drives in a RAID 1 for storing all of my data. I'm thinking about buying another 500GB Hard drive, putting the OS volume in a RAID 0, and reformating the 2x750GB Hard drives also in a RAID 0, and using time machine to backup the 2x500GB drives to the 2x750GB drives. Is having two RAID 0 arrays possible in a Mac Pro? (I don't have a raid card) is it ok to have the backup volume to be a RAID 0? (seeing as how if One hard drive fails, I can replace it easily within a few days) I do need the OS volume to be on a RAID 0 array, because I run Final Cut Studio, so I need the extra speed offered from a RAID 0. If it was possible to run a RAID 5 with 4x750GB hard drives I would do it, BUT I don't think that I can run a RAID 5 without a raid card, and I don't want to spend the extra money on one)
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2008 Mac Pro RAID / Backup question
- Thread starter iamwhoiamtoday
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RAID 0+1 or 1+0 perhaps?
http://patternbuffer.wordpress.com/2008/02/17/bootable-software-raid-01-10-in-mac-os-x/
http://patternbuffer.wordpress.com/2008/02/17/bootable-software-raid-01-10-in-mac-os-x/
You can do RAID 0 and RAID 1 in software on the Mac Pro. RAID 5 requires a physical card.
I imagine you can have two RAID 0 arrays, but backing up a RAID 0 to another RAID 0 is kind of counter-productive since a RAID 0 loses all data once one drive fails. Now, I understand the chances of dropping one drive in each RAID 0 stripe set at the same time is a bit unlikely, but stranger things have happened and if it does happen, then all of your data is gone.
I intend to run my Mac Pro with a 1TB boot drive (OS X / Win64 / Apps) and then three 1TB drives in a software RAID 0 which will be backed-up via Time Machine to an external storage array (2GB to start and then add as necessary).
I imagine you can have two RAID 0 arrays, but backing up a RAID 0 to another RAID 0 is kind of counter-productive since a RAID 0 loses all data once one drive fails. Now, I understand the chances of dropping one drive in each RAID 0 stripe set at the same time is a bit unlikely, but stranger things have happened and if it does happen, then all of your data is gone.
I intend to run my Mac Pro with a 1TB boot drive (OS X / Win64 / Apps) and then three 1TB drives in a software RAID 0 which will be backed-up via Time Machine to an external storage array (2GB to start and then add as necessary).
RAID 5 gives you fault tolerance. You need a minimum of 3 drives to create a RAID 5 set. Parity information is spread across the drives so if one fails it can be replaced and the data rebuilt from the parity data stored on the other healthy drives.
I have a 4 disk RAID 5 volume in a NAS at home. I have 4 1 TB drives which gives 3 TB of storage and 1 TB of parity information. You do lose some storage space but I have extra piece of mind if a disk fails. I don't fancy losing 3 TB of videos and music.
RAID 1 doesn't offer fault tolerance.
Check out http://en.wikipedia.org/wiki/RAID for a more detailed description of the different RAID levels.
RAID-0 with dual 500GB HDs is a really good setup. That's what I am using on my Mac Pro...so far, so good. REALLY really fast. You need identical HDs to do this setup in the Apple disk utility. I am having a good experience with it so far on my rig, it's sped up everything tremendously.
The only risk (as people will tell you) with RAID-0, when one HD goes down, you lose your whole system. But if you regularly backup, it's not a problem.
Also, this setup is relatively cheap. You can get a good 500GB HD on newegg for $99, maybe $89 now. So basically under $200 for the RAID0 if you choose this setup.
I can tell you, it's very, very fast and will make a 2.8GHz machine feel like a 3.2GHz machine or faster. I used to not think disk meant alot vs. processor, but I feel otherwise now. Disk speed is vital, as you will see in the SSD setup....look at the new MacBook Air. The SSD is much faster.
But, I'm talking RAID-0 (striped dual HD RAID) - you take 2 HDs and pair them to make one array. It writes to both equally and reads to both equally simultaneously. I wouldn't expect a 2x or 100% speed increase, but look for about 60-70% faster than using a single HD. I've proven this in xBench tests when running a base single HD system when running the RAID0 and looking at the disk test.
Apple HD utility is good, but Hardware HD is faster. Still, I think the Apple Disk Utility works well (it is for me) and I would recommend it to anyone if you can get a couple of cheap 500GB or 750GB HDs and turn them into a RAID0 system, then use this as your boot disk.
Good luck,
-Ward
The only risk (as people will tell you) with RAID-0, when one HD goes down, you lose your whole system. But if you regularly backup, it's not a problem.
Also, this setup is relatively cheap. You can get a good 500GB HD on newegg for $99, maybe $89 now. So basically under $200 for the RAID0 if you choose this setup.
I can tell you, it's very, very fast and will make a 2.8GHz machine feel like a 3.2GHz machine or faster. I used to not think disk meant alot vs. processor, but I feel otherwise now. Disk speed is vital, as you will see in the SSD setup....look at the new MacBook Air. The SSD is much faster.
But, I'm talking RAID-0 (striped dual HD RAID) - you take 2 HDs and pair them to make one array. It writes to both equally and reads to both equally simultaneously. I wouldn't expect a 2x or 100% speed increase, but look for about 60-70% faster than using a single HD. I've proven this in xBench tests when running a base single HD system when running the RAID0 and looking at the disk test.
Apple HD utility is good, but Hardware HD is faster. Still, I think the Apple Disk Utility works well (it is for me) and I would recommend it to anyone if you can get a couple of cheap 500GB or 750GB HDs and turn them into a RAID0 system, then use this as your boot disk.
Good luck,
-Ward
Thank you very much for your input. I'm going to go ahead and order my second 500GB Drive for my OS Drive (RAID 0)
As far as backups go, now much would a 4-drive NAS cost me? This NAS would have to be able to support 4x750GB Hard Drives in a RAID 5, AND have a GigE port. Links would be appreciated
As far as backups go, now much would a 4-drive NAS cost me? This NAS would have to be able to support 4x750GB Hard Drives in a RAID 5, AND have a GigE port. Links would be appreciated
Try this NAS - 4 drive bays, Gigabit Ethernet, MAC compatible around $400
http://www.promise.com/product/product_detail_eng.asp?product_id=177
Promise is now selling on the Apple store, Promise VTrak E-Class 8x 750 SATA RAID subsystem, it replaces the XserveRAID which Apple no longer sells.
Is Promise supplying the RAID card for the Mac Pro also?