2008 Mac Pro RAID / Backup question

RAID 0+1 or 1+0 perhaps?

http://patternbuffer.wordpress.com/2008/02/17/bootable-software-raid-01-10-in-mac-os-x/

 

Which Raid config do you recommend and do i need a Raid card and if so which should i get

 

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).

 

Do i need a card for 0+1

 

Do i need a card for 0+1

 

sorry double post
and what is the advantage of RAID 5

 

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.

 

what is parity?

 

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

 

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?