If you run Startup Disk Creator, you'll notice that it does three (four) things:
- Format the drive
- Copy over the data from the ISO to the drive
- (Add an extra casper1 file for persistence, if selected.
dd
does not give you persistence.)
- Install a bootloader
It is not a GUI for dd
(there are GUIs for dd
, but SDC is not one of those).
You can think of it as doing equivalent of Arch Linux's or Gentoo's manual methods. You should be able to create a bootable USB using most (reasonably popular) distros' installation ISOs at present. This was not true about three or four years ago, when I looked at Arch. It was only 2010 that all Arch ISOs gained this feature (where you could write it directly to a USB drive) - from 2008 to 2010 they had special USB images.
Further, if you dd
a drive directly, that drive is effectively read-only until you format it or use the remaining space somehow. A SCD-created disk is still usable as a USB drive, even though the contents are are not accessible from the live environment easily. So if you dd
a 1GB ISO to a 8 or 16 GB USB drive, you're effectively abandoning the remaining space unless extra steps are taken.
1Typically, most live images use a SquashFS file for the root partition. SquashFS is read-only, so for persistence, a casper-rw
file is created in /casper
. I am not sure of the origins of casper
. From what I understand, when booted with the boot=casper
option, the kernel overlays the casper file (creating one if none exists) on top of the squashfs, so that it gains write capability. casper
doesn't have to be a file, it can also be a partition.
Best Answer
Go to your Unity Dash, locate "Startup creator" and create a bootable installation USB disk using it. You will of course first download the *.iso image. Make sure that your USB is recognized when you plug it in, so that the creator knows which drive to use.
Then boot your computer using the USB.