Ubuntu – Any way to manually make a bootable USB from ISO

bootisounetbootin

I've been using Unetbootin but it occasionally fails to create a bootable usb the way I need it to, especially with the newer versions.

Is there a way I could extract the iso myself?

Best Answer

This is a bit destructive, but works all the time. It will write everything to the /dev/sdb (which is the usb device. )

sudo dd if=/path/to.iso of=/dev/sdb bs=16M

read the manpage of dd

1: Download Ubuntu

2: Convert the ISO file

Convert the .iso file to .img using the convert option of hdiutil

hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso

Note: OS X tends to put the .img ending on the output file automatically.

3: Determine the media to install

Run diskutil list to get the current devices. Insert your USB and the run again diskutil list. The new device its your USB.

4: Install into the USB

Unmount your device (not physically) with diskutil unmountDisk /dev/diskN where N is your USB number and execute

sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m

Notes:

Using /dev/rdisk instead of /dev/disk may be faster
If you see the error dd: Invalid number '1m', you are using GNU dd. Use the same command but replace bs=1m with bs=1M
If you see the error dd: /dev/diskN: Resource busy, make sure the disk is not in use.Start the 'Disk Utility.app' and unmount (don't eject) the drive

5: Eject

Run diskutil eject /dev/diskN and remove your flash media when the command completes.

6: Boot

Restart your Mac and press alt/option key while the Mac is restarting to choose the USB stick.

Ubuntu – Convert bootable USB to ISO file

To create an image from a drive

sudo dd if=/dev/sdx of=/path/to/new.iso

Alternatively, to create a USB drive from an image

sudo dd if=/path/to/iso of=/dev/sdx

Replace /dev/sdx with your USB drive, e.g. /dev/sdc.

WARNING: It is imperative that you make certain you are using the correct drive. If you don't use the correct drive, you could lose your data. To check your currently mounted drives, use the command lsblk.

Note: Copying large files (1 GB or higher) can take a long time, be patient.