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I have a broken DVD drive and no others available right now to burn a DVD iso to so I'd like to use a empty hard disk instead.

I've tried Unetbootin but that only copies a few megabytes of files - the rest of the image data in the ISO is ignored.

I have verified the ISO is valid and working with VirtualBox. It's MD5 hash is also as expected. But I need to boot at the real BIOS not an emulated one.

I've also tried things like:

sudo cat /disk/image.iso > /dev/sdb1

and that got "Permission denied" - no idea why.

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what distro? unetbootin only works on casper based distros...also, what OS do you have running now? –  Journeyman Geek Sep 10 '11 at 21:03
No guarantees, but you might try using dd instead of cat. Note that it has a special syntax. –  zpletan Sep 10 '11 at 21:44
@Journeyman_Geek The OS in question may or may not have been mystery OS 'X' ;) I'm not sure it's true unetbootin only works on casper based dsitros though –  Luke Stanley Sep 17 '11 at 21:47
@zpletan thanks for the DD reminder, it worked enough, in the end. –  Luke Stanley Sep 17 '11 at 21:48

4 Answers 4

up vote 4 down vote accepted

In the end I used dd and a USB stick as a boot disk because somehow booting didn't seem to work for the dvd on the hard disk.

sudo dd if=/storeM/os-dvd.iso of=/dev/sdb bs=8M

sudo dd if=/storeM/bootdisk.img of=/dev/sdc
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For information, since this hits a lot of people using sudo while writing to a file. Here's what happens if you use the cat command:

sudo cat /disk/image.iso > /dev/sdb1

is interpreted by the shell as executing sudo cat /disk/image.iso and then sending output to /dev/sdb1. Only the cat command is privileged; the output redirection isn't.

dd avoids these problems since source and target are arguments and part of the privileged command.

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Thanks for that point. –  Luke Stanley Jul 25 '12 at 0:15

You can use MEMDISK to boot an optical image from a hard drive.

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And of course the site is currently down... –  Ignacio Vazquez-Abrams Sep 10 '11 at 19:22

I would consider downloading the file again, also check the integrity, there is a reason you're facing errors. I've never had a problem with UNetBootin.

You can also try Universal USB Installer if you have a Windows system spare. EasyBCD also has an option to insert an ISO to be bootable from the Windows Bootloader, the iso can be executed from memory or the hard disk but is experimental.

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There is no integrity problem, I validated it's MD5 is as expected. Universal USB Installer didn't work. I will try EasyBCD. –  Luke Stanley Sep 13 '11 at 5:14

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