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I have a bootable Linux compact flash card and want to copy it to an SD card. What would be the easiest way to do this?

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  1. Boot up a copy of Linux that isn't your CF Linux. Open a terminal emulator.
  2. Run fdisk -l and find your CF card and SD card (they may have identifiable sizes or labels). I'll assume that they're /dev/sde and /dev/sdf.
  3. Run dd if=/dev/sde of=/dev/sdf.

And don't forget to backup your hard drive. Every time someone wipes their hard drive from a mistype, another fairie dies.

If the extreme power of dd is too much to handle, you may find CloneZilla a bit more manageable.

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Not fairies but bogons die - once the ones left can be overpowered by cluons, enlightenment has been achieved. – mlp Aug 24 '11 at 2:11
dd if=/dev/CF of=/dev/SD

But seriously, to be able to meaningfully answer your question we need to know more about

  • relative sizes of the two devices
  • how the CF card is partitioned, if indeed it is
  • what bootloader you're using
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Both the CompactFlash and SD card are 4GBs. The CompactFlash appears to have 3.5GB partition that I can see in my Ubuntu box. The bootloader is Ubuntu. I tried a dd on these and it doesn't seem to copy the part with the bootable system files as it won't boot when I use the SD card. I guess a dd won't copy the partition I would have partition the SD card and then run the dd? – user208861 Aug 24 '11 at 21:04
@user208861, edit your question to add those details, and also the commands you've tried and what appeared to happen. – mlp Aug 31 '11 at 4:16
dd does what it's told, so if you specify if= and of= as the whole-device files for their corresponding devices, then it will copy the bootcode. See digitxp's answer. – mlp Aug 31 '11 at 4:20

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