If you use multiple hard disks, you can use Apple RAID (Redundant Array of Independent Disks) to optimize their storage capacity, improve their performance, and increase reliability in case of a disk failure.

http://docs.info.apple.com/article.html?artnum=152065

Before you do anything, talk to us here or others on the pro's and con's of a RAID setup for your needs.

Mirroring (RAID 1) immediatly writes the same data to both drives at once, this includes corruption, mistakes, viruses/trojans, bad installs etc. It only protects you against a rare hardware failure. People have reported problems mirroring their boot drives, they can't boot from it or use it.

Cloning is better

With cloning you make a clone to another drive, when you want. It copies everything, most copy protection, system setup, everything at once. This gives you a added benefit of time to check out a new software update or install before commiting.

Also if your boot drive goes down for any reason, you can simply Option boot off the clone and be just fine, repair the boot drive or reverse clone.


Striping (RAID 0) takes two or more drives and splits the data across the drives, increasing performance greatly.

Problem is if one drive goes down, you lose the data on all drives. It's only good for a scratch disk, and having a backup of the data is a must.

The more drives in a RAID 0 the more risk you take. Plus you get into a bottleneck with channels, you need to install PCI cards to increase the amount of channels to the drives. The more channels and more drives the more speed.

Apple's X-RAID works with a Apple Fiber-Channel PCI card you install in your G4/G5. It has multiple channels to bring the data to the RAID unit itself, which has it's own RAID options as well.

(It supposely gets 400 MB per second writes, now that is very very fast!)

There are other RAID setups that combine features of stripping and mirroring, requiring a great amount of drives and channels to get speed and redundency. But simple striping and mirroring is what you'll find in Apple's Disk Utility.

My suggestion is to talk to us before you do anything! You may wind up being very unhappy.

Can this be done with one 160GIG HD & one 250GIG HD both SATA 7200RPM set @ Raid 0 & also as a boot disk? If so what are the steps I need to take to insure the procedure is done properly?

Thank you

If you set up a RAID 0 with two different sized drives, you will end up with less space overall, as it will use the smallest drive size for the array. This means that in your setup, you would end up with 320 GB instead of the 410 GB that you have available to you now.

Just some food for thought.

Thanks for the speedy reply I was thinking about what you said and thought OK if 320 is all i could get with raid 0 then could i partition them fist making the 250 into 2 parts one 160 & one 90 & only raid 0 set the org. 160 & the 160 split from the 250 and leave the remaining 90 alone?

Thanks Again! :mrgreen:
ICRAZY

No wonder you use the name "icrazy"

I'm not sure if that would work. I have not heard of anyone doing it, or even trying it. IF you had good backups, you could try it and let us know how it goes

Two drives, one a boot, application and bare "home" and the other for files is better than partitioning.

When you partition and if the computer needs data from the other partitions obviously a bottle neck will occur as you only have one head reading the data.

Also the heads have to travel back and forth across the drive to each partition.

The solution is a fast boot drive and a larger slower stock drive.

The OS and apps needs a lot of different files in random order, the file drive just goes to what it needs and reads the whole thing.

Also keeping changing files off a boot drive will keep it optimized longer. No "holes".

I am currently using Retrospect for automated file backups and network backups, but this doesn't really help me if the server is the one with the hardware problems.
What do you recommend using to clone my boot drive and how to I choose on boot?

...thanks to one of Sailfish's posts. Carbon Copy Cloner.
http://www.bombich.com/software/ccc.html
A great GUI port of linux's ditto.

I have one raid stripped with 3 500 gb hitachi drives,
that's internal in my G5 dual 2.5... Works great.

Now I'm going to use a MiniG with 4 more Hitachi 500Gb drives that will run off the same card that the internal Raid 0 runs from (no problem to do).

The dilemma,
I want to back data up that sits on the Raid 0 (not a good place for anything important).
Should I set the 2nd Raid as a mirror for the raid 0 (Back up 0) or set it as 4 individual drives and just keep the data on them (no Back up).

Sailfish said to check here before doing anything and I need the input anyway even if he didn't suggest it.

Hoping to hear some feed back.
Thanks

If you want to backup the internal RAID 0, then any way you set the externals up will be fine as a backup. However, if you want the backup to be "safe", RAID 1 is the way to go.

If you have four drives in the external miniG, you can setup all four as a RAID 0 or two pairs of RAID 1, correct? (per their website)

.

If you have four drives in the external miniG, you can setup all four as a RAID 0 or two pairs of RAID 1, correct? (per their website)
That's correct.

Can you pick and choose what on the Raid 0 you want backed up or are stuck with the whole ball of wax?

What does a Raid 5 offer in the mix?
Thanks I need the dialog here.