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View Full Version : mkbootdev and rw access to USB key



leeja
01-01-2007, 03:55 PM
I ran the mkbootdev script to create a bootable USB key, and it worked perfectly. I can boot from the USB key without any problems and I can see the files that the script created on the USB key in Linux and Windows; however, I would like to make the USB key read-write so I can save files on it while running Knoppix. I tried the 'mount -o remount,rw /cdrom; mount --bind /cdrom /mnt/sdb1' instructions listed in http://www.knoppix.net/wiki/Bootable_USB_Key (with the device name changed to match the one listed by Knoppix for my USB key) and it appeared that I was able to write to the device. Unfortunately, when I rebooted my computer it did not recognize the USB device as bootable, and I could not read any of the files in Linux or Windows. Is there a difference between the way the mkbootdev script works and the Bootable_USB_Key instructions that would cause the USB key to be unbootable after writing to it, or am I using the wrong mount commands? Any help would be greatly appreciated.

Krellan2
02-01-2007, 06:01 PM
I ran the mkbootdev script to create a bootable USB key, and it worked perfectly. I can boot from the USB key without any problems and I can see the files that the script created on the USB key in Linux and Windows; however, I would like to make the USB key read-write so I can save files on it while running Knoppix. I tried the 'mount -o remount,rw /cdrom; mount --bind /cdrom /mnt/sdb1' instructions listed in http://www.knoppix.net/wiki/Bootable_USB_Key (with the device name changed to match the one listed by Knoppix for my USB key) and it appeared that I was able to write to the device. Unfortunately, when I rebooted my computer it did not recognize the USB device as bootable, and I could not read any of the files in Linux or Windows. Is there a difference between the way the mkbootdev script works and the Bootable_USB_Key instructions that would cause the USB key to be unbootable after writing to it, or am I using the wrong mount commands? Any help would be greatly appreciated.

Those mount instructions are good for only one bootup only. They are only good for your current Knoppix session. Once you shut down and reboot, they will be lost, and you will have to give the mount instructions again the next time. The mount instructions do NOT affect how your USB key will be recognized and booted up. Maybe if you made a mistake while the USB key is mounted read/write, and erased some important files that are necessary for booting up, but this is not very likely.

As for getting your computer to recognize your USB key when booting up, that is the hardest part. It's all about the BIOS. On the Bootable_USB_Key page, there are a sequence of steps you can try, near the bottom of the page. Please try ALL of them.

My computer is weird in that it will only recognize a USB key when turned on from a cold start (power off completely then power on). My computer will NOT recognize a USB key at all when just rebooted, either from software or from hitting the reset button! Strange.

There are other quirks in other computers, I have found. One computer at my work will recognize FAT16 only, and not boot from FAT32-formatted USB keys, at all, even if everything else is identical (same size, same partition layout, same boot sector). I have noticed the mkbootdev script always uses FAT32. That is at least one difference I have found.

So, please try ALL of the suggestions listed. Many computers have quirks like these.