USB Booting

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USB booting can be a hit-or-miss process with DSL or other pendrive-based operating systems.

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BIOS

Older computer BIOS usually do not support direct booting from a USB device. Around 2001, PC motherboard manufacturers started to add USB boot support.

There are two common BIOS methods for direct USB booting:

One method is called the "USBHDD" method and it is used to support the booting of standard USB mass storage devices that are configured like a normal PC hard drive.
The other method is called the "USBZIP" method and it supports booting from a USB storage device that behaves like the original IOMEGA ZIP drive with USB support.

Most computers (just about all Dells, for example) made today have a BIOS that supports the USBHDD method so I expect that this will eventually become the standard way to boot a USB device. However, many motherboards will support BOTH methods, and many older motherboards have USBZIP support.

Some newer BIOSs which support USB 2.0 will not boot from an older pen drive. Using a USB 2.0 compliant one usually solves this problem. Also, some older BIOSs which only support USB 1.1 will not boot the newer drives which support USB 2.0!

If your computer does not seems to recognize your USB pen drive greater than 500MB, it is possible that the motherboard has the recognition set to "auto", which means it will treat pen drives less than 500MB as "Floppy", and greater than 500MB as USBHDD. Try to find the option "Force FDD", to allow you pen drive to be treated as USBZIP no matter its size.

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Boot floppy

In any event, just about any computer that has an available USB port will support booting from the DSL USB boot floppy. See the boot floppy section of the WIKI for more info.

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Localization and installation

From within the DSL LiveCD [1] main menu, it is possible to create either a USBZIP or a USBHDD formatted pendrive with DSL installed. Just choose the appropriate install method and follow the prompts. Also see Installing to a USB Flash Drive

Most USB pendrives are located at device name "sda" after they are plugged into the USB port. Be careful: many new serial ATA drives are also named "sda".

However, you can verify this location by typing this command inside a terminal window:

     dmesg | grep scsi -A 3

and it should tell you the device name for your USB (SCSI emulated) devices and vendor name.

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USB Booting from Grub (not directly from BIOS)

You can boot DSL from an existing GRUB without altering your BIOS settings. You could investigate by yourself what options to add, but with this you should be fine. Note that if Grub is protected with password, then you can't follow this procedure.

When you are on the GRUB screen, press c, then write the following:

  grub > root (hdX,Y)


  grub > kernel /linux24 root=/dev/sdZN init=/etc/init

  grub > initrd /minirt24.gz

  grub > boot

Where, X it's your usb stick and Y a partition number starting with 0. You can press the tab key from your keyboard to see a list of available disks, as the following:

  hd0, hd1, ...

You can also guess, if you don't know which hd above is your pen, by pressing tab again after choosing one of the hd0, hd1,..., etc. Another list will shown up to you with the partition information of the selected disk, numbered starting with 0. That number, that correspond to a partition, it's our Y named above. You can do this with all the devices and then conclude which one is your pen.

Generally speaking (if you don't need to map your devices) Z will be a letter as follows:

Suppose that you have a list of available devices:

  hd0, hd1, ..., hdN

Start counting with letters starting with a from the first sata disk (if there is) to the pendrive. The letter you reach is the Z you replace. Note that if there aren't sata disks, Z will be a.

And last, N will be N = Y + 1.

Example:

Suppose you have two disk: a primary pata, and a secondary sata. You boot your pc, and insert the pendrive. Suppose also that hd0 is your primary disk, hd1 your secondary disk, and hd2 your pen. Then, our Z will be b as a it's the secondary disk hd1, which is sata.

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Update

How to update a previously installed flash DSL.

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MyDSL

Your MyDSL applications (*.dsl files) should be saved into the /cdrom directory if you would like them automatically booted off of the USB device upon bootup.

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