RAID0 array - still use IDE slaves?

stingray2

Senior member
Jan 11, 2001
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Shuttle AK35GTR, AMD 1800+, 1gb DDR 2100, many harddrives.
my mother board has onboard raid (highpoint raid, 372), so i have
4 ide ports (2 can be used for RAID). i just set up a RAID0 array on my system.
by connecting 2 80gb ATA133 hard drives, each as set to master, and each
connected to a different IDE connector (RAID2/IDE4, RAID1/IDE3).
i set up the RAID0 arrary in the bios, and then booted to my primary HARDDRIVE,
connected to IDE0 connector, which has WinXP installed. I then formated the
RAID0 array (NTFS). I then disconneted my primary harddrive, and rebooted
using the WInxp cd, and installed it to the RAID0 (now 160gb). since i had
another ATA133 80gb drive, i wanted to use it, and connected it to the RAID1/IDE3
as a slave. everything boots ok, but any substained use of the non-raided 80gb
hard drive causes my system to hang, and i/o errors on that drive.

so, my question is. if you set up a RAID0, you then cant use / connect any other
drives as slaves, and not using them as part of the RAID0 ?
did that make sense? in otherwords, if you set up a RAID0, using 2 drives, you
now have 2 slave ports that are not usable for anything other then in a RAID0-1? or RAID5 config?

thanks.
 

Smilin

Diamond Member
Mar 4, 2002
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The thing you want to avoid if possible is having more than one device per channel when using raid.

You want your Stripped or Mirrored drives to each be a Master on IDE 3 and 4.

If you add drives put them on IDE 1 or 2 as either a master or slave. Ideally you want this lone-drive to be on it's own channel as well if possible but it's not as important.

The only time it's 'acceptable' to have slave drives on IDE 3&4 is if you are doing a 4 drive array (Raid 0 or Raid 10). You will take a bit of performance hit when it's setup like this but it will work.

The underlying reason for all this crap is: IDE can only handle one read OR write request at a time. In a 4 drive raid setup all drives are doing the same thing (read or write) at the same time so nothing is left waiting. If you do a 2 drive array and then put an individual drive in there as a slave, you can get in the situation where one drive in the array has finished an I/O request while the other one hasn't even started because the slave has been occupying the bus.

Go SCSI raid and you won't have this trouble (You'll just be broke!$!$!)
 

Nothinman

Elite Member
Sep 14, 2001
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Slave drives aren't recommended because IDE doesn't multiplex requests to the disks like SCSI can. Any time an IDE drive is servicing a request the whole wire is locked until it finishes, think of it like IDE is simplex and SCSI is duplex (well, you can have up to 15 devices on recent SCSI controllers so 'du' is misleading).

So if you have 2 disks on the same wire in the same RAID 0 set you defeat the entire purpose of the RAID 0 set because each request has to wait on the other to finish anyway, you'll probably get some performance increase because of the slow seek time on the IDE disks but it won't be much. And you still run the same risk of data loss because you're using RAID 0.
 

stingray2

Senior member
Jan 11, 2001
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thanks.. your answers are what I had assumed, but could not find documented anywhere.
 

Beeker25

Senior member
May 28, 2000
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One a RAID Array is set up on the onboard RAID controller and onboard IDE Connectors connected to that IDE RAID controller, you can only attach HD's that are going to be in the RAID array that you have created, meaning that you cannot attach a Slave HD onto the IDE RAID Connectors on the motherboard and use it as just a single slave drive in the system, it has to be part of the RAID array if it connected to the IDE RAID connectors when a RAID Array is present. The only place to attach that extra drive is on one of the Primary or Secondary IDE channels that are not connected to the onboard IDE RAID controller, otherwise, you will just have to add it to the RAID Array. RAID 0 is asking for trouble, I will warn you now. I have an EXTREME amount of experience with RAID-SCSI RAID, but RAID none the less, see my System Rigs in my sig. RAID 0 is the most unsafe RAID to use, if you loose 1 drive in the array, you loose ALL of your data, completely unrecoverable. So either don't store anything on there that is extremely important that you don't want to take the chance of loosing, or make sure you back it up on a regular basis. I even back up all of my RAID 5 SCSI Arrays to Tape backup for extra security and safety. Hope this info helps.
 

Pierceheart

Junior Member
May 26, 2001
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I have a variant to this question:

I am building a new system first time dealing with raid. Not taking my old hard rive to the new system so I am going from SCRATCH.
I have an iwill xp-333r and 3 maxtor 30GB ATA 133 7200rpm drives.
Is it possible to do an install of winME DIRECTLY to a raid array, and if so, how do you set up the raid array in the first place?
Or, do I need to install my OS onto ONE drive on ch 1 or 2, install raid controller drivers in winME, then ghost my boot drive to the raid array?
What would you all recommend as my best avenue of approach on this system? Buying a 4th HDD is not an option at this time.
Basically, i am looking for the simplest way to install an OS clean, and have the os on a raid array.
 

nemo160

Senior member
Jul 16, 2001
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pierceheart-
you should be able to install directly onto the two raided drives, go into the raid bios as your booting up, set up the drives as a raid 0 or 1
reboot and boot from the install cd
i've only done this under 2k, but while the install is starting it will give you the opportunity to install the raid drivers by pressing a certain key (f6 i believe), use the raid floppy that came with your mobo to install them
just to keep things a bit simpler, don;t attach the 3rd drive until after you get your os installed to the raid, and when you attach it..put it as master on first channel, dvd as slave, burner as master on second channel
don;t try and put 3 drives into the array..the raid controller is only 2 channel and a 3 drive raid 0 would be slower than a 2 drive, a badly setup raid array is slower than a single drive
raid 5 is ideal for 3 drives, more secure than raid 0, faster and more capacity than raid 1, but requires an expensive hardware raid card, so basically you'll want to go either 0 or 1, 1 if you have critical data, 0 for a bit more speed...but back up early and often
all that said, consider going to a more robust version of windows than me, 2k and xp are much more stable and reliable, much better memory management, when i ran under 98se with 512mb windows behaved quite oddly..xp...super solid and smooth