Hardware raid problems under Linux

Bosco

Hi there,

I have a problem getting a Highpoint 1520 SATA RAID controller working on an i865-based mainboard under linux. I hope someone can help.

When trying to install the latest version of Debian the installer tries to autodetect IDE devices and fails, preventing the DVD drive from mounting and blocking the rest of the install. If I plug out the raid controller and try again everything works fine, and so I was able to install onto a harddisk via the mainboard's onboard SATA controller. I thought I'd be able to add the raid controller driver manually after the installation had finished but when I plug back in the controller the machine halts on boot with 'kernel panic' messages.

I then tried to install Fedora Core 4 but that produces kernel panic messages before it even reaches the IDE detection stage, raid controller plugged in or not.

My questions:
Has anyone installed any recent linux distribution onto a 1520? Was there any problem with IDE detection?
How common or otherwise is it for the addition of a PCI card such as a raid controller to cause problems like kernel panics on boot?
Should I try other distros or am I likely to find the same problems with them all?

Any help at all is much appreciated.

Bosco

Something I should have mentioned...

The system works perfectly under Windows so there are no major hardware faults.

Red Alert

a lot of the highpoint raid cards are not true hardware raid, they're sitting on the fence between a plan software raid and a real one as they do have some level of hardware accelerator for the XOR calculations needed on a RAID-5 array. you are really better off ditching it like i did and getting a real raid controller like a 3ware one.

leeroybrown

As Red Alert mentions, the cheap highpoint or promise cards are generally not proper hardware RAID controllers. They fall into the camp of 'fake raid', where a driver is required to deal with the reading/writing at an operating system level.

TBH, you'd probably be better off with a linux soft raid implementation as it'll be no slower (I presume you're going for a RAID1?) and more reliable. Or is it just a case of using the controller to get extra S-ATA drives into the machine?

Bosco

Windows is currently installed in a partition on a two-disk Raid 0 array on the Highpoint. There are a further two disks connected to the mainboard's onboard SATA controller. Initially I'd hoped to install Linux in a partition on the array but at this stage I'd be content to have Linux on one of the standalone disks without it being aware of the Highpoint at all.

I'll be doing a college project using Java and PostgreSQL in the near future and I thought I might learn something by working on Linux seeing as both work on it. The system still needs Windows however as it's primarily a games machine and so it would be easier to just forget about Linux and work with Windows than it would be to buy a new controller.

What I'm really trying to find out is why Linux doesn't like having the controller plugged into the system. I know next to nothing about Linux and so it's difficult for me to determine if my problem is purely OS-related or if there is some underlying problem that just doesn't happen to effect my Windows install.

Anyway thanks for the help guys

leeroybrown

If you already have a raid container exported from the RAID controller it will be assigned a device ID by linux when it boots up.

Is there an error along the lines of 'unable to mount root file system' when you boot up with the RAID card installed. If there is I would reckon that the RAID controller is being assigned device id's for it's containers before the onboard SATA. Thus the filesystem that linux expects to be /dev/sda1 on a SATA drive turns out to be part of a RAID container on a RAID card...

You could try booting your linux install with command line options to make it look for the root filesystem elsewhere (perhaps /dev/sdb,...).

NutJob

Red Alert wrote:

a lot of the highpoint raid cards are not true hardware raid, they're sitting on the fence between a plan software raid and a real one as they do have some level of hardware accelerator for the XOR calculations needed on a RAID-5 array. you are really better off ditching it like i did and getting a real raid controller like a 3ware one.

This is true i had the same problem with Sli Serial ATA raid.
Its all just "Fake RAID". The windows drivers actually do the raid work and access the disk throught the PATA controller in my case.

Yet another abuse of VXDs to cut hardware costs. Your best option is a real RAID controller as i couldnt get soft raid on Linux to read the disks :eek:

Bosco

Sorted this out this week...ish. My issues turned out to be:

1: My kernel version didn't support my card. Was able to install Suse Enterprise 9 (kernel 2.6?) which works fine with the Highpoint card.

2: I didn't understand how Linux and bootloaders address hard disks. There's a line in my LILO config that maps device names to BIOS drive IDs. Changing the hard disk boot order in the BIOS affects these IDs (for me 0x80 - 1st HDD, 0x81 - 2nd HDD etc.). I didn't realise that every time I'd change the boot order I was inadvertently breaking the bootloader's config and preventing Linux from booting.

Thanks for the input folks