48 lines
2.1 KiB
Plaintext
48 lines
2.1 KiB
Plaintext
The proper mode to boot a USB key drive in is "USB-HDD". That is the
|
|
ONLY mode in which the C/H/S geometry encoded on the disk itself
|
|
doesn't have to match what the BIOS thinks it is. Since geometry on
|
|
USB drives is completely arbitrary, and can vary from BIOS to BIOS,
|
|
this is the only mode which will work in general.
|
|
|
|
Some BIOSes have been reported (in particular, certain versions of the
|
|
Award BIOS) that cannot boot USB keys in "USB-HDD" mode. This is a
|
|
very serious BIOS bug, but it is unfortunately rather typical of the
|
|
kind of quality we're seeing out of major BIOS vendors these days. On
|
|
these BIOSes, you're generally stuck booting them in USB-ZIP mode.
|
|
|
|
THIS MEANS THE FILESYSTEM IMAGE ON THE DISK HAS TO HAVE A CORRECT
|
|
ZIPDRIVE-COMPATIBLE GEOMETRY.
|
|
|
|
A standard zipdrive (both the 100 MB and the 250 MB varieties) have a
|
|
"geometry" of 64 heads, 32 sectors, and are partitioned devices with a
|
|
single partition 4 (unlike most other media of this type which uses
|
|
partition 1.) The 100 MB variety has 96 cylinders, and the 250 MB
|
|
variety has 239 cylinders; but any number of cylinders will do as
|
|
appropriate for the size device you have. For example, if your device
|
|
reports when inserted into a Linux system:
|
|
|
|
usb-storage: device found at 4
|
|
Vendor: 32MB Model: HardDrive Rev: 1.88
|
|
Type: Direct-Access ANSI SCSI revision: 02
|
|
SCSI device sda: 64000 512-byte hdwr sectors (33 MB)
|
|
|
|
... you would have 64000/(64*32) = 31.25 cylinders; round down to 31.
|
|
|
|
The script "mkdiskimage" which is supplied with the syslinux
|
|
distribution can be used to initialize USB keys in a Zip-like fashion.
|
|
To do that, calculate the correct number of cylinders (31 in the
|
|
example above), and, if your USB key is /dev/sda (CHECK THE KERNEL
|
|
MESSAGES CAREFULLY - IF YOU ENTER THE WRONG DISK DRIVE IT CANNOT BE
|
|
RECOVERED), run:
|
|
|
|
mkdiskimage -4 /dev/sda 0 64 32
|
|
|
|
(The 0 means automatically determine the size of the device, and -4
|
|
means mimic a zipdisk by using partition 4.)
|
|
|
|
Then you should be able to run
|
|
|
|
syslinux /dev/sda4
|
|
|
|
... and mount /dev/sda4 and put your files on it as needed.
|