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r204d
12-27-2004, 03:09 AM
I would appreciate any help that you guys could give. I've been trying to 'dd' an image onto a usb drive from a booted machine running knoppix 3.7... and I'm hitting an arbitrary limit to the file size that I can transmit. If I transmit over say a 43MB file, it doesn't appear to transfer. The machine sees the USB drive and I've successfully copied the smaller files, but I'm trying to copy the entire filesystem.

Thanks in advance for any tips.
-r204d

markpreston
12-27-2004, 08:00 AM
Question: Why did it say "out of disk space" when copying to the flash drive, even though the size of the files to be copied is less than the free space on the drive?

Answer: Some flash drives are formatted with the FAT12 or FAT16 filesystem. This is inefficient. If there are a lot of small files, the flash drive may fill up much more quickly that you might expect. There are two ways round the problem:

The first way is to archive the files onto the flash drive. To archive means to create one big file instead of lots of small ones. To create an archive, click K menu, Utilities, Ark (Archiving Tool). The second way is to reformat the drive to a more efficient filesystem, such as FAT32.


Ref.
http://unit.aist.go.jp/itri/knoppix/knowing-knoppix/main/index9.html
Hope this helps.
Regards,
Mark

r204d
12-27-2004, 03:37 PM
Mark,

Thanks for your reply. I appreciate any help. I should have provided more details. The USB harddrive that I'm sending the files to is 160 GB. The filesystem on it is Win FAT32. What I'm trying to do is dd an entire filesystem from a 10 GB harddrive. I thought maybe it had to do with my setup. Knoppix seems to plug and play the USB interface, but in scanning throughout the forum it seemed like most people were booting Knoppix first, and then editing the FSTAB file and then issuing a mount command. The mount setup is the only thing which felt was in question to me, but then I'm also new to Knoppix. Regardless I got to a threshold where when I could only successfully dd a file that was less then 43/44 MB. I literally had the successful and unsuccessful commands side by side.

OErjan
12-27-2004, 08:37 PM
why use dd?

cp -afx /mnt/hdXY/filename /mnt/usbdisk/directory/
or even

cp -afx /mnt/hdXY/directory/* /mnt/usbdisk/directory/
will work, first wil copy one file at a time. second everything in directory (and files below...)
a few limits are:
not files over 3.95Gb
that NO permisions... are needed, fat can't handle those, if they are needed use tar. to make one file (somewhat like an uncompresed zip).
if you are trying to MAKE a image file larger than 43Mb on that disc i have no idea what the trouble is. i use a usbdisk regularly with 700+M files (knoppix, Slackware, Debian... iso's).
the disk is 120Gb, and yes it is fat32.
what does
dmesg|grep sd say? or
fdisk -l