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JBruyet
2nd November 2008, 05:27 AM
Hey all, I was just trying to install Fedora9 on my computer (with an Asus M2N-SLI Deluxe motherboard) and Fedora can't see the raid array setup on the board. When I get to that point of the install Fedora sees all of my hard drives as individual drives. I've tried mirroring, striping with mirroring and raid 5 but Linux still sees each drive individually. Oh, unless I remove the raid, then one of my drives disappears. I was going to setup a raid array in the LInux install but I didn't know how to do it. I could probably figure it out but I still would like to know what the problem is with the raid setup on the motherboard. Googling the problem didn't help. Anyone have any ideas?

Thanks,

Joe B

Wayne
2nd November 2008, 05:30 AM
Please don't use bold/large fonts in your posts, unless there is something you need to emphasise.

Wayne

scottro
2nd November 2008, 01:51 PM
Did you enable RAID in the BIOS? I'm not familiar with that board, but many of these MB's have a host raid type setup rather than an actual true hardware RAID.
(though from your comment that then one of the drives disappears, it seems as if you covered that.)

I guess it's simply a matter of needing a driver for that particular RAID. This can be annoying, and it's a bit unusual these days too, as RH is such a common server platform.
I would poke around the manufacturer's site for a RAID driver and see if they have one for Fedora. Most server MB's come with a CD that will provide both Linux and Windows RAID card drivers.

JBruyet
4th November 2008, 03:16 AM
Well then I need to move to "Plan B." Maybe I'll look into getting a raid card for SATA drives.

Bummer,

Joe B

scottro
4th November 2008, 05:22 AM
It is a bummer, and frustrating.

If it's server hardware, then the manufacturer will, very very often, have RH and/or SuSE drivers as they seem to be the biggest platforms in the US and Europe. In the US, for an x86 or x86_64, or ia64 (errm, is that right? I'm really tired tonight, but if it's not, hopefully you know the one I mean) will have RH drivers.

If it's simply a high end MB but not really server oriented, then it becomes a gamble. Good true hardware RAID cards are expensive too, though you can get the cheap host RAID type ones cheaply, and often, they will be RH compatible and marked so on the Vendor's site.

JBruyet
4th November 2008, 05:02 PM
Yeah it's a bummer, and yeah it's frustrating, but at least I'm seeing more Linux drivers being put on device CDs. That's gotta be a good sign. I've used Linux off and on over the last couple of years but I haven't really dedicated any serious time to getting to REALLY know Linux. Now I think it's a good time to get to know Linux.

I checked on the Asus site and they don't have any Linux drivers for the raid. I checked into some SATA raid controller cards and found them to be a bit more then what I wanted to pay, but I'll probably get one anyway. I do too much work at home to not have some fault tolerance built into my servers. Thanks for the help.

Thanks,

Joe B

JBruyet
5th November 2008, 01:05 AM
Hey wait a second... Can I build a raid array from the inside once Fedora 9 is installed and working? Kinda like I can do with a Windows server? If so is there a tutorial somewhere for that?

Thanks,

Joe B

PabloTwo
5th November 2008, 03:56 AM
Does this link (http://codeidol.com/unix/fedora/Advanced-Installation/Configuring-RAID-and-LVM-During-Installation/) help?

tiendn
5th November 2008, 04:01 AM
Select Drives:
Make sure your Diskette Drive (3.5 floppy) is set properly (Usually set to Internal)
Make sure that "Drive 0: SATA-0" drive is set to "ON"

Go to "SATA Operation":

Your system proabaly came set to "RAID Autodetect / AHCI" - THIS SETTING CAUSES YOUR SYSTEM TO GO INTO AN IDE LOOP AND DOESN'T ALLOW IT TO FIND YOUR FACTORY INSTALLED SATA DRIVE.

CHANGE THE SATA OPERATION SETTING TO "COMBINATION"

Reboot - make sure that the boot sequence is set to CD rom before HD and make sure that the reinstall CD is in the drive. Setup will load, hit enter to reinstall FC. Your HD should now be detected and you should see the licensing agreement.

If you have your files backed up I reccommend deleting the partition and reformatting prior to installing XP, it will give you that option after the license agreement.

Once you have successfully reinstalled the OS, some mb reccommends that you change the SATA Operation setting back to RAID AUTODETECT / AHCI (or back to whatever your factory setting was) to avoid any problems with other IDE devices installed on your system.

Hope that helps!

Good luck!

Linux (http://www.linux-archive.org/)

LBCoder
5th November 2008, 05:19 AM
That board, despite what the manufacturer says on their website, does NOT HAVE RAID. It has only standard controller(s). They may include a device driver that provides FAKERAID, but it is certainly NOT a function of the hardware.

Hardware and software raid devices each have their own advantages and disadvantages. This fakeraid has none of the advantages of either and all of the disadvantages of BOTH. As such, you should do your best to avoid it, regardless of what OS you use.

When you are installing fedora on the system, you have the option to set the partitions manually. Included with this option is the ability to configure SOFTWARE RAID.

Note that software raid is on a by-partition basis, unlike hardware raid, which is on a by-disk basis. That means that if you want a raid set for your /home partition, you create a partition on each device and add them to the raidset.

stevea
5th November 2008, 07:14 AM
LBCoder is right. Most SOHO type MOBOs only have "fakeraid". A real RAID controller consts hundreds$$ more. This means the BIOS has code that allows you to present the OS an interface that looks like a RAID. Usually this means you have an Intel bridge part. with SATAs. All the work is done in software from the BIOS.

I have an ASUS P5B-Deluxe and the fakeraid works perfectly with Fedora Linux - no problems.
Be certain your BIOS settings for RAID are correct and enabled.

I performed many benchmark of fakeraid versus the normal Linux software RAID on this board (some are posted on this forum). The Linux RAID is microscopically faster, but it has other advantages. If your MOBO breaks your fakeRAID disks cannot be re-assembled by another MOBO (except the same BIOS/setup, ICHn part). If your Linux RAID breaks you can just install the disks on another Linux system and recover easily. Also the Linux drivers for the actual SATA can have some scheduling optimization that is not available for the BIOS fakeraid.


Hey wait a second... Can I build a raid array from the inside once Fedora 9 is installed and working? Kinda like I can do with a Windows server? If so is there a tutorial somewhere for that?


There are many tutorials on Linux software RAID. Here is one:
http://www.tldp.org/HOWTO/Software-RAID-HOWTO.html
But do use "http://www.google.com/linux" to search for more.

You can actually create the Linux software RAID during the Fedora Installation. Choose "custom disk configuration" and then create some same-size partitions to build a RAID from (typically on differnet disks!). The new/edit menus let you merge these into a RAID, and then you can take the RAID partition and assign it to "/" (root) or other mountpoints. The /boot partition cannot be RAID since grub bootloader doesn't understand software RAID.

Also note that LVM (the logical volume manager) has a nice striping and mirrorig ((roughly the same as RAID0, RAID1) which is simple to use. system-configure-lvm is a nice gui interface for LVM. The LVM is lower performance than the software RAID, but has many other advantages - especially for a server app. Read the LVm tutorials too.

DeCSS
5th November 2008, 07:47 AM
Oh man, I went through this for DAYS with a customer's server. I drove myself crazy trying to figure out how to get it to recognize the RAID. Finally I phoned the manufacturer for the RAID card, only for them to tell me that the linux drivers for the RAID had to be compiled and installed after the OS was already installed! I was not happy.

Anyway, what I finally ended up doing was loading the OS on a seperate SATA drive and then loading up the drivers for the RAID. It worked. Not ideal, but it worked.

stevea
5th November 2008, 07:51 AM
Oh man, I went through this for DAYS with a customer's server. I drove myself crazy trying to figure out how to get it to recognize the RAID. Finally I phoned the manufacturer for the RAID card, only for them to tell me that the linux drivers for the RAID had to be compiled and installed after the OS was already installed! I was not happy.

Anyway, what I finally ended up doing was loading the OS on a seperate SATA drive and then loading up the drivers for the RAID. It worked. Not ideal, but it worked.

No -that's not the same problem - that was a real RAID controller.. OTOH once you create a module for the driver (and the specific kernel) you should be able to slip it into the installer w/o a lot of trouble. Kind of a PITA, but ...

JBruyet
5th November 2008, 05:58 PM
Hey, thanks to all the help! I've made the install but I haven't done any additional program installs yet. I think I'll go back and redo the install and setup the raid like was mentioned above. The need for some fault tolerance AND my need for more practical experience with Linux helps drive that choice.

Again, thanks to all for their input,

Joe B