Linux USB

Set bootable flag on USB drive

$ sudo fdisk /dev/sdb   #/dev device needs to be a hard drive(sdb) not a partition(sdb1)
Command (m for help): a
Partition number (1-4): 1
Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

$ sudo fdisk -l                                                                   
<--- output omitted ----->
Disk /dev/sdb: 2002 MB, 2002747392 bytes
255 heads, 63 sectors/track, 243 cylinders, total 3911616 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *          63     3911615     1955776+   c  W95 FAT32 (LBA)

Format USB stick

sudo fdisk -l   #find out your usb device
df
umount /dev/sdb1
mkfs.vfat /dev/sdb1   #create fat32
mkfs.ext3 /dev/sdb1   #create ext3
mkdosfs -F 32 -I /dev/sdb1 #format device to fat32

Copy .iso on USB stick to make bootable

This works only with hybrid ISOs images. The resulting USB stick will act exactly like a liveCD/DVD. of= (output file) value needs to be a hard drive (eg. sdb) not a partition (eg. sdb1).

sudo dd if=image.iso of=/dev/sdb
sync

Convert .iso to hybrid image

Starting in version 3.72, ISOLINUX supports a "hybrid mode" which can be booted from either CD-ROM or from a device which BIOS considers a hard disk or ZIP disk, e.g. a USB key or similar. To enable this mode, the .iso image needs to be postprecessed with this utility. Note that old .iso images prior the supported version will not work.

isohybrid image.iso

This will append necessary information to the image file therefore the check-sum will change.

Mount .iso

sudo mkdir /mnt/isoimage
sudo mount -o loop -t iso9660 image.iso /mnt/isoimage/