• Choose a category
• All
• Classic-Fiction

When working with Promise controllers, it's important to choose the ataraid driver and not the FastTrak driver. The ataraid driver is open source and was developed by Arjan van de Ven of Red Hat. The FastTrak driver is a binary-only driver and is distributed by Promise. Licensing aside, the main difference between the two drivers is that the Promise driver uses the SCSI subsystem to interface with the Linux kernel. That means Promise's binary-only driver needs to perform additional steps to translate commands between SCSI and ATA. Conversely, the open source driver uses ATA directly and is consequently faster and more stable.

* * *

Tip

If you are using the SuperTrak controller, the same semantics I describe here will apply, but the SuperTrak controller uses a different driver, also available from Promise. The SuperTrak controllers are also reported to work using Linux's Generic I2O Driver. Your mileage may vary.

* * *

When using the FastTrak driver, I experienced many system lockups and slow-downs (all non-fatal) while performing normal, low-impact disk operations such as editing files and listing directories. You'll notice many associated entries, as in the following code listing, either in the system logs or printed on the console:

FastTrak : Drive Interrupt Time Out.(1)

FastTrak : RESET Channel1 * DEV1(OK)

FastTrak : Drive Interrupt Time Out.(3)

FastTrak : RESET Channel2 * DEV3(OK)

FastTrak : Drive Interrupt Time Out.(3)

FastTrak : RESET Channel2 * DEV3(OK)

These messages indicate that I/O commands have timed out before they were completed. The controller must reissue the commands to ensure data integrity. These timeouts can also result in low-level seek and read errors on individual member disks and cause the system to become unstable, requiring a cold reboot. Using the ataraid driver eliminates these problems, and it should always be used in lieu of the binary-only FastTrak driver.

Unfortunately, most distributions do not currently support direct installation using the ataraid driver. That means you'll need to use Promise's FastTrak driver disk to install Linux from scratch, and then rebuild the kernel with support for the ataraid driver. If you are adding a Promise ATA RAID controller to an existing Linux system, you can simply rebuild the kernel so that it includes the ataraid driver and begin using the new controller. The I/O issues associated with the FastTrak driver can cause filesystem errors between system reboots. If possible, choose a journaling filesystem such as ext3 or ReiserFS during the installation process. This will save you from some additional headaches if you have to reboot the system a few times before you can upgrade to the ataraid driver. Chapter 6 discusses filesystems.

Creating a driver disk

You should download the driver disk appropriate for your distribution from the Promise web site (http://www.promise.com). A section of the web site is dedicated to Linux support. Driver disks are provided for Red Hat, SuSE, TurboLinux, and Caldera's OpenLinux. On my Red Hat system, I downloaded the zip file for RedHat 7.1/7.2/7.3 (T-FTS-02-RHD73.zip). Included in the archive are two additional zip files: one file for uniprocessor (rhup-ftb22.zip) systems and one file for multiprocessor systems (rhsmp-ftb22.zip). Use the following commands to prepare a blank disk and unpack the archive. (Note that this example is for a single-processor Red Hat system.)

# mkfs.msdos /dev/fd0

# mount /dev/fd0 /mnt/floppy

# unzip rhup-ftb22.zip -d /mnt/floppy

# sync

# umount /mnt/floppy

Installation

Now you can begin system installation. Boot the new system with your installation media and choose the option that lets you specify additional drivers. For Red Hat, that means typing linux dd at the boot prompt. When prompted for the driver disk, insert it, and the FastTrak driver will load. After a few moments, the installer will execute normally.

During system partitioning, arrays defined on Promise controllers will show up as SCSI disks, a by-product