RAID 0 startup

Thinking of using 500GB and 750GB internal drives for a raid 0 startup disc (software raid obviously), any ideas/problems?

yeah either use a raid 0+1 solution, or back up your raid 0. raid 0 just spans the data across 2 drives for performance, raid 1 mirrors 2 drives so if 1 fails, the other is still there. so raid 0+1; raid 0: stripes your data across 2 drives for performance and raid 1 mirrors this on another drive. you would effectively need 3 drives (or partitions) e.g 2 250gb for raid 0 and another 250gb to mirror this but as you are looking to use the apple utility, this is software raid so if the boot drive dies, you still would lose everything. I suggest having another smaller drive for osx, have this in a raid 1, (2 drives) and data on a raid 0+1 so 5 drives in total. Geeez. Not that I have as many...
Luck...
Daniel

Similar Messages

Mirrored Raid on Startup Drive?

Can I set up a Mirrored RAID with my Startup Drive without loosing the data?
I have a G5 Dual 1.8 running the latest OSX. I want to add a second internal HD, then setup a Mirrored RAID from my Startup Disk to my newly installed second internal drive. How do I set up this RAID without loosing anything on my startup drive? The new Drive will be the same size as my startup drive. I want the second drive as a backup startup drive.
Kevin Hawkins

Hi Kevin Hawkens;
What do you expact to gain by having a mirrored RAID?
Allan

Software RAID as startup volume

I want to get 4 velociraptor hard drives for my mac pro. If I create a software RAID 0 in Disk Utility, and reinstall Leopard on that volume, can I use it as a startup volume? If you can, does it take longer for the computer to startup?
Thanks

Firstly, I'm assuming that you have an extra external disk for time machine. So in order to restore to the raid, maybe instead of using time machine clone it using superduper. Just to maybe make things easier. Clone the your boot volume to the external, create the raid of all 4 hds in disk utility, then once it's made clone back the boot volume from the external to your raid.
For superduper:
www.shirtpocket.com
But just to reiterate, (and adding to what hatter mentioned) maybe a couple larger 640 or 1 TB Western Digital Blacks might be better, instead of all VRs. You could maybe use 1 VR for your boot drive, and like 2 or 3 WD blacks(if that's what you want to do). 3 x 1TB Blacks might serve you better as you are using video apps.
Or if speed is your main concern, maybe an external enclosure might be a better fit. Sonnet, Firmtek, etc. Raid the drives on the external (using hardware or software raid) and use the internal slots for backup. Of course this will cost more, however it would probably be better for you down the road, especially since you are working with video.
http://www.amug.org/
They have some good reviews for external enclosures.

RAID 0 Questions - advice needed

I am stepping up to a new BTO Mac Pro (2.8Ghz with 8GB third-party RAM) and considering the Apple RAID Card vs. Software RAID. I have a few questions regarding RAID 0 on the startup volume and hardware vs. software RAID. I am a graphic designer and running Adobe CS3 and working often with pretty large files.
1. Does RAID 0 on a startup volume offer any performance boost if working data is on another volume? Does the working volume need to be in RAID 0 or RAID 5 to reap the performance beneftis. This is a point I am not entirely clear on yet.
2. I understand the risks of running RAID 0, especially on a startup volume. Any advice on whether or not this offers any real world performance boost?
- OR -
Would a single Raptor offer similar results. Or better yet, would a partial-stroked 500GB SATA II disk offer the same results as a single Raptor at a fraction of the cost, without the RAID 0 risks?
2. Is a hardware RAID card (i.e. the Apple RAID Card or better yet, the new CalDigit RAID Card for less $$$) a better option than software RAID (either Apple or SoftRAID)? With a RAID 0 startup volume and a RAID 1 pair for storage, will hardware RAID offer any performance gains? Or would a single startup volume with a 3-disk RAID 5 storage volume be a better option (I know RAID 5 is not possible with software RAID).
3. Any advice/feedback on the Apple RAID Card? I have read some horror stories about battery charging, at least initially. I have not seen much about the strange recharge cycle which apparently can cripple your machine for days every 3 months. The new CalDigit RAID card appears to be very promising. Supports the 4 internal drive bays as well as external drives, which the Apple card does not.
Thanks in advance for any help/advice.

I usually avoid linking to other forums, but in this case, there is a similar discussion over on MacNN forum setting up a Mac Pro to use RAID.
Apple RAID software has continued to improve. The difference in performance between Apple and SoftRAID has narrowed to the point both are excellent. SoftRAID though alerts you on any I/O time out or read/write errors, and use a stripped read which is nice, when or where it is needed.
I've never stopped upgrading and trying to improve on performance. The trick is not everyone can go out and spend $800 for a drive case and controller plus another $500 on disk drives for an external setup, and buy 3-6 drives for the existing SATA ports.
Rather than buying the fastest, I bought some 160GB RE WD drives, cheap, good for RAID, and planned to use those as the base. Then got the 320GB model. Then bought WD RE2 500GB $115 ea , which seems to be a nice price and still does nicely, optimized for writes. That means I can do some mix-and-matching.
Some can take their existing SATA drives to get started. And probably has some drives that can be used for backups and such.
Here is my own shopping list:
Sonnet Tempo E4P:
http://eshop.macsales.com/item/Sonnet%20Technology/TSATAIIE4P/
SeriTek Case: $525
http://eshop.macsales.com/item/Firmtek/SATA5PM/
Or something cheaper,
http://eshop.macsales.com/item/Norco%20Technologies/DS500N/
Dual bay case to use with 2 ODD ports and NewerTech kit:
http://eshop.macsales.com/item/Other%20World%20Computing/MESATATBEK/
http://eshop.macsales.com/item/Newer%20Technology/MPQXES2/
(takes some work to access those two ODD SATA ports, but worth it, always on)
OWC XLR8 Specials, usually have Friday specials:
http://eshop.macsales.com/Specials/XLR8YourMac.cfm
10K Raptor $210 vs WD RE2 750GB $220 if you look under hard drives.

10.3 Server new install won't boot from Mirrored RAID - HELP!!

Hi all,
I had 10.3 Server running fine on a 450 MHz B&W G3 (home server use, nothing too demanding), when I decided to add a 2nd HD and run the server from a RAID mirror (both 80GB drives). I had problems enabling RAID on the boot drive with diskutil in Terminal, so I decided to rebuild the server. I didn't have much besides the system on it, so backing up data and re-installing isn't a big ordeal (or so I thought).
No problems creating the mirror set once I re-formatted the drives. The install seemed to go fine (10.3.4 on install disk), but upon restart, I got the flashing system folder/question mark. When booting from the install disk, Disk Utility recognizes the RAID, and Startup Disk recognizes the mirror as a viable boot drive and allows me to select it and restart. Same problem, no system found.
When I run diskutil info for the mirror, it lists the mirror volume as Not Bootable.
I've checked the disks with both Disk Utility and DiskWarrior - all looks OK. I've reset PRAM and NVRAM, taken out added PCI cards, and disconnected all FW and USB devices (besides kbd and mouse).
Unfortunately, B&W G3 can't boot from an external FW drive, so I'm stuck with booting from a CD/DVD for troubleshooting.
My next step is to re-install on a single drive again and try to enable RAID and mirror, but I'd sure like to avoid that if I could.
I've searched through this board and didn't really see this particular situation. Any of you smart server folks seen this before -- any ideas or suggestions??
TIA,
Brad
B&W G3 Mac OS X (10.3.4) 450 MHz, 10.3 Server, 80GB RAID mirror

if you backup your data from a NON-RAID Drive (Single drive), create a RAID array and then Restore from the backup you created... you will find you cannot boot from the drive.
Apparently the sector or drive header information in a non-RAID drive is different than in a RAID array... so when you restore the backup data from the non-RAID drive to the new RAID Array; you effectively corrupt the RAID array not allowing it to be booted from.
The solution is to create the RAID array and then re-install your system from scratch... copying over the data you want to keep from your initial backup one file at a time (don't do a complete system copy or you will once again, corrupt your new RAID install).
I had the same problem and it took me a great deal of time to figure it out.
Joe

Possible to boot B&W G3 from mirrored RAID??

Hi all,
I've tried to get my B&W, running server 10.3.9, to boot from a mirrored RAID (RAID 1). So far, I can successfully create the RAID, run the software installer, and choose the RAID with Startup Disk, but upon restart, it doesn't recognize a valid system (flashing system folder/question mark).
There's a tech article that states the B&W G3 won't boot from a striped RAID (RAID 0), but I've not been able to find anything definitive regarding mirrored RAID. Does anyone know for sure (or know where I can find documentation)?
TIA,
Brad
B&W G3 Mac OS X (10.3.9) 10.3.9 server

Thanks for the info. I had no problem either creating the RAID (successfully in both Disk Utility and Terminal), installing the OS, or selecting the RAID pair as the startup disk. I'm doing this with ATA disks.
Once done, though, the system won't boot from the RAID pair. I know that the B&W open firmware won't allow startup from striped RAID (technical article http://docs.info.apple.com/article.html?artnum=58258 applies), but don't know if this applies to mirrored RAID as well.
Has anyone out there successfully booted a B&W G3 from a RAID 1 configuration?

Lion update 10.7.5 crashed my Mac Pro

After completion of the 10.7.5 update from the Software updater, my Mac Pro would not boot from the 10.7.5 startup drive. I have 4 hard drives in the machine. A 1TB startup disk running Lion, two 1.5TB drives in a mirrored RAID config with OS X Snow Leopard (the last Apple OS that would allow a RAID'd startup drive), and a 3TB disk configured as a Time Machine backing up the other three drives. I've been wrestling the problem for over a week now. So far I've observed:
I do not think its a bad hard disk:
I bought a new 1TB Seagate drive to replace the failed 1TB Western Digital thinking I had a hardware problem. The Seagate loaded Lion 10.7 fine and booted fine, until downloading the 10.7.5 update from the "Software Update" in System Preferences. Same result. Dead computer as soon as the install completed and attempted to boot. The crash screen is solid grey with a text warning in the middle that reads something like hit a key to try again. It's an infinite loop from there...multiple failed boots leading to "hit a key to try again."
Curious thing, I can use the failed drive, just not as a startup disk:
So I pulled the Lion drive and booted from my old RAID'd pair running Snow Leopard. Ran great, except of course all the applications that no longer run in Snow Leopard etc. I set Snow Leopard as the startup disk, and rebooted with the Lion drive pushed back in. System booted fine into Snow Leopard and I could see the Lion drive, open it, move files around etc.
Mountain Lion didn't work either:
Then I thought, well, I wanted to move to Mountain Lion anyhow, no time better than now! I formatted the Seagate that had the bad 10.7.5, and installed a fresh copy of Mountain Lion. Guess what? Same result. Infinite loop of grey screen of death. But like before, if I booted into Snow Leopard, I can look into the Mountain Lion disk like I could with Lion 10.7.5.
Stuck with 10.7.4:
Next step was another format of the Seagate. Re-installed Lion 10.7, but this time only updated it to 10.7.4 (vice 10.7.5). Now I'm going through all the pain of restoring with Time Machine, reconfiguring software, and typing in keys.
The final situation is still worse than I was before I started:
Somewhere along the line, bluetooth stopped working ("bluetooth not available"), even after trying a SMC reset. Also, I think mutliple initializations of my apple ID in the cloud resulted in password insanity on our iPhones and iPad...even after typing in a password, they only seem to work for a day before I get another pop up on my iPhone that my passord is wrong.
Maybe the "incremental" 10.7.5 will work?
Apple released the 10.7.5 update on 19 Sep 12. This is the update that caused all this pain. I noticed there is an incremental update to 10.7.5 released 4 Oct 12. Does anyone know if it will fix all this? I'm not to excited about pushing the "I believe" button again...
Frustrated in the Corn Fields,
Jeff Brown

I have had exactly the same problem on my older 17" MBP. (I think its a 2009) Upgraded from 10.7.3 >> 10.7.5 necessary to synch with Iphone etc and on powerup you simply get the screen "You will need to hold down the power button....
Formated, Re-installed and PRAM's all to no avail.
Finally downloaded Mountain Lion and created Boot USB, again performed clean install, this time 1/2 way through the installation (Im guessing after it has created the rescuse sector and re-boots) it came up with Grey Screen - Computer needs to re-boot itself.
Was able to continue the installation however whenever it booted up it would come up with the same grey screen - computer needs to re-start....
Now after 3 days I have returned to Lion 10.7.3 frustrated and £13.xx out of pocket, unable to synch with Iphone
Grrrrrrrr

Mac Pro - Separate HD for OSX and Windows?

Hello Mac Pro users - maybe some of you can help...
Are going to buy a Mac Pro soon - which will be used for graphic artwork and Windows games. Today I have a Mac and a PC - for the same purpose - and now I want to build the Mac Pro with a harddisk for OSX - and another harddisk for Windows (XP or Vista). Is it possible to have 2 separate HD's (or more) with each systems using the standard setup by Bootcamp - or do I have to make a partition on the OSX HD and then install Windows there?
I'm asking this pro forum because I can't get a clear answer here in Denmark where I live - a Apple supplier first said it was impossible - then 2 days later, that it was possible, but they will charge me for 2 hours of support - and in another forum some have told me it was easy - but have given me no help how to do it - and again some have told me to use some software called "rEFIt".
So is it possible - and hard to do?
If possible, please tell me in steps how to do...
BR FLASH

Boot Camp will allow you to
utilise an entire disk for Windows. If you go to the
Boot Camp web page you can actually see it in a
picture…
http://www.apple.com/bootcamp/
The only thing you need to be wary of is that the
Boot Camp Assistant will not wrok from a Mac OS X
installation that is on a RAID set. As long as you
boot mac OS X from a single drive then it's really
easy.
I had a setup for awhile of two drives in RAID-0 for my Startup drive, a backup single drive, and a separate 300GB drive just for Windows.
In Windows the "Startup" drive in Control Panel would not show the RAID-0 Startup volume, but I could startup from it by hitting Option when it rebooted.
Steve

Can't boot in safe mode - RAID startup disk

hi ..
my macpro has a mirrored RAID as a startup disk (using HD bay 1 & 2) ... i am trying to boot into safe mode but this does not work at all, even when holding down the shift key it starts up in normal user mode.
Is there a way to do this ? is it maybe possible to boot into safe mode with a terminal command ? or any other way ?
thx for any help with this ...

Hallo
This topic is quite old, but I face exactly the same issue.
My MacPro tries to boot in safe mode, but restarts and boots in normal mode afterwards.
There are messages in system.log that indicate to me that the kernel exensions on the boot helper volumes are different from the ones on the main partition:
Dec 19 21:06:11 localhost kernel[0]: Got boot device = IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/SATA@1F,2/
AppleAHCI/PRT2@2/IOAHCIDevice@0/AppleAHCIDiskDriver/IOAHCIBlockStorageDevice/IOB lockStorageDriver/ST3750640AS P Media/IO
GUIDPartitionScheme/AppleRAID_OfflineV2_Untitled3@2/AppleRAIDMember/AppleRAIDMirrorSet/RAID@0
Dec 19 21:06:11 localhost kernel[0]: BSD root: disk3, major 14, minor 11
Dec 19 21:06:11 localhost kernel[0]: [Bluetooth::CSRHIDTransition] switchToHCIMode (legacy)
Dec 19 21:06:11 localhost kernel[0]: [Bluetooth::CSRHIDTransition] transition complete.
Dec 19 21:06:11 localhost kernel[0]: [HCIController][configurePM] power parent ready after 1 tries
Dec 19 21:06:11 localhost kernel[0]: AppleIntelCPUPowerManagement: initialization complete
Dec 19 21:06:17 localhost kernel[0]: can't remove kernel __LINKEDIT segment - in-kernel linker needs it
Dec 19 21:06:17 localhost kextd[11]: in-memory mkext doesn't match on-disk mkext; non-boot kexts won't be loaded
I tried:
sudo kextcache -v 6 -f -u /
Which updates the kernel extensions on the boot helper volume,
but it does not work.
As for the firware updates, I could still install those booting from external FW disk.
Patrick

Mac Pro 3,1 (early 2008) RAID card hangs at startup

Hello,
I have a Mac Pro 2.8Ghz Quad Core (early 2008) with 10GB RAM and 512MB VRAM.
I have noticed that the Mac Pro RAID card hangs at startup for RAID volumes.
It seems to start okay with a single boot drive (have used both WD Raptor 150GB 10K and Seagate 'factory' 320GB 7200rpm as boot drives...)
But the RAID 0 array using two factory 1TB WD 7200rpm is what seems to hang at startup. I have run Disk Warrior, Disk Utility and RAID Utility and found no major errors...
Any suggestions? Have already replaced the RAID Card battery with OEM part.
Thanks!

Say good-bye to the Apple Pro RAID card. It started its life as a $999 card to support SAS/SCSI and/or RAID5.
Then the problems with 2.5TB drives, battery, and does it really do something and add to your system.
I would use SoftRAID and create a 3-drive mirror of 2TB drives instead.
And an SSD for the system.
Seems like those are some very old drives.
I have a lot of the 150GB 10K VR drives, and some 300GB along with older 74GB and a couple of the Raptor series. Loud and while solid I would use for spare boot drives, clone only.
Backup your data, pull the RAID card, and restore to the drives. And clone the system onto a 250GB $109 SSD. $139 buys a 400MB/sec writes and 800MB/sec reads Samsung PCIe-SSD XP941. None of my SCSI 15K drives would come close.

RAID w/2 USB Drives Startup Problems

I have an internal 750GB HD and I have been backing up to an external 500GB using SuperDuper. I am getting close to 500GB on the internal and with money being tight I bought a 250GB External to RAID with the 500GB using Disk Utility using RAID type Concatenated Disk Set. This seemed to be what I wanted to do, gave me all the disk space, was able to use with SuperDuper and it even shows up under StartUp Disk. However, I can't get it to StartUp from the RAIDed external drives. Please Help me Obi-Wan..hehe sorry I couldn't resist. Any ideas please let me know. Thank you in advance.
Darrin

Actually, you can format and have multiple partitions and drag volume names into the RAID tab.
I've seen a couple people with problems with WD MyBook 500GB models, and they were using FW interface on Mac Pro, so I would guess it is the bridge that WD uses.
And, USB is not "ideal." You also want each drive in a mirror on its own channel, and there isn't a lot of bandwidth - which you must share with all other USB devices.
You should be able to mirror an internal drive and ext. FireWire.
Any errors on one drive get copied to 2nd. Useful for someone that doesn't know to backup but otherwise... also, SoftRAID 3.6 ($149) would probably do a better job but overkill. It also alerts you immediately if there is an I/O error of any kind.

Is this how I stop getting a RAID error message on startup?

I have been looking around trying to find out how to resolve an error message I get - just looking to see if you can help me by letting me know if I have this correct...
I (not mine actually, but have use this Mac Pro while I work on a project) have an Apple RAID card, and on startup get this message..
"The Apple Raid Card installed on your system required your attention"
And usually within a few minutes the black curtain comes down and I need to restart.
If I simply clear the error events log in the RAID utility, will I no longer get this message?
And secondly - in the RAID utility, the bottom left corner has an almost empty battery and a yellow light - am i supposed to wait till this goes green (charged) before I ever restart or shut down the Mac?
As you can probably tell I have little Raid knowledge...
Cheers
Hugh

If the battery status on Raid Utility is showing yellow or not completely charged then you should definitely leave the computer on til it's completely charged and showing green. I have the Apple Raid Card in my 2008 Mac Pro 2.8 8 core. The FAQ's say that the battery reconditions itself every 3 months or so. Mine seems to do it more often. Probably cause I don't leave it on 24/7 and don't use my Mac Pro every day.
Try leaving the computer on overnight. It shouldn't take that long to charge. After it's done charging and shows green for the status, clear the message status and you should be good to go.

RAID's as Startup Disks

Actually several questions in that. I've cobbled together three basically useless old external firewire drives into on 500G unit that is actually useful. My goal is to move my massive iTunes library to that (I have a Time Capsule for backup, so the issues of data loss are prepared for). However, I WAS using one of those tiny drives to have a copy of the system software, and a couple of utilities (onyx and Disk Warrior) as quick way of getting the system up and running if I have a problem. I want to install snow leopard on the new raid drive, but the installer won't find it. Is this because you can't use a raid as a startup drive? Or is it that it's all old firewire drives? Or is the problem something else entirely?
Any thoughts would be appreciated.

You don't need hardware RAID. In fact hardware RAID is very limited when it comes to booting a Mac. The closest are probably a 4-drive or dual drive enclosure with built in RAID bridge, but that isn't hardware RAID.
http://eshop.macsales.com/shop/hard-drives/RAID/Desktop/
Listed in the profile is PowerBook G4 listed along with 10.6.x by the poster, which are way off.
Without a controller though you are asking to share the FW bus single channel which doesn't make much sense or have bandwidth. Any of today's drives can saturate a FW800 connection.

Can RAID array be bootable startup?

I have a striped RAID array that I have connected to my iMac by Firewire 800, an external USB drive using USB 2.0, and another external HD connected on Firewire 400. Using SuperDuper!, I've been trying without success to make bootable clones on these three HDs. Even though the cloning seems to go well, when I hold down the option key on startup, the drives don't show up. Are these configurations all capable of being bootable startups? Any suggestions on why they don't show up?

Hi William, Happy Holidays!
Supposedly they are, but I've never actually tried the FW/USB combo Raid, tried both seperately in RAID, Which, BTW, I would not recommend, the longest I've had a RAID go is 6 months before destructing themselves beyond recovery.
Also, I should point out that a single FW/800 Boot drive will be faster than a FW/800 USB combo Raid due to the slowness of USB2. I get around 69 MB/Sec with FW/800, and 29 MB/Sec with a 4 drive USB2 RAID, around 20NB with a 2 drive USB2 RAID!

Virtual Disk on non-startup RAID?

I have my stock 250G as start-up, but I have 1 terabyte RAID 0 (500x2) as my second drive. Can I get the OS virtual swap drive to use the RAID drive rather than the startup drive? Or, does the Mac work better just left alone with the startup drive? Thanks.

Most attempts to do so are iffy and can break at some point, while most users try to have enough RAM so that pageouts are minimal.
OS X starts by using a default 64MB swap file, then adds 2nd, next time uses 128MB, then 256MB, etc. So they may not be in the best location - especially on a 1TB RAID volume.
So there are programs (OS X maintenance utilities) that use to, or do, some have removed the feature to move swap files to another drive (volume) and attempts to find an improvement in performance are minimal at best.
If you had created multiple RAID partitions, and a small 2.5GB? volume just for swap... maybe. And OS X Apple Disk Utility can have multiple RAID partitions on a set of drives. - You have to first create the partitions, then select a pair of matched partitions from each drive for the RAID volume, rather than using the drive name in the "create RAID" window.
I would rather see someone use a 10K Raptor dedicated boot drive rather than mess with this, or, buy more RAM.

RAID 0 startup

Similar Messages

Maybe you are looking for