This how to explains how to create and use a Live USB drive.
Note: Lines beginning with "$" indicate commands you should type (do not include the $; this represents the command line prompt); subsequent lines represent typical output. You will need to run some commands as root.
System Requirements
- A working computer running Fedora or Windows
- A USB Flash Drive with 1 GB or more of storage space (also known as a USB Storage Stick, USB Thumb Drive, or Jump Drive)
Ability to boot from USB media
Though most modern ones can, not all computers can boot from USB media, due to different BIOS settings and system capabilities. If your computer cannot do so, this procedure will not be useful. If you are not sure and don't mind downloading an installing an image on your USB drive (possibly wiping it of data), the only risk is wasting some time.
If your USB stick is not in working order, this procedure may fail. Watch for error messages during the process.
Some flash drives may not be bootable by default, even if your hardware is capable of doing so. You may need to mark the partition bootable or you may just need to reformat the flash drive. See "Errors and Solutions" below for more information.
Check the size of your USB device
Many USB sticks indicate the size on the packaging or the outside of the device.
If you don't know the size of the device, or want to check it for data, you should be able to auto-mount the USB device by inserting it into a USB port. You can check the contents and size using the graphical file manager. In Linux, you can also use the command line:
$ df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/VolGroup00-LogVol00 143G 14G 122G 10% / /dev/sda1 99M 12M 82M 13% /boot tmpfs 1009M 0 1009M 0% /dev/shm /dev/sdb1 3.9G 4.0K 3.9G 1% /media/usbdisk
USB drives are usually mounted in /media. In this case, the device is /dev/sdb1 and has a 3.9GB capacity, and is almost empty.
Take note of "/dev/sdb1" or equivalent; you will be specifying the device name if you use the command line method.
How to repartition and format flash drive
CAUTION: This will erase all data on the USB drive!
If the drive has not been partitioned properly (or if you are unsure), use fdisk to repartition it. If the drive is not new, a repartition and reformat is recommended.
It is also possible to do a non-destructive installation of a LiveUSB image, if you have sufficient empty space. (See "How to install non-destructively" below.)
The fdisk command must be run as root. Include only the drive name in the command, not the partition number. Be sure to select the correct disk, or you may erase important data! Check the output of "df -h" if you are unsure. For example, if your partition will be /dev/sdb1, do:
$ /sbin/fdisk /dev/sdb
If you don't have fdisk installed, run "yum install util-linux-ng" as root.
The following session output from fdisk shows the responses to give to the prompts. The line starting Last cylinder ... refers to the size of the flash drive, so may be different than in the example.
Command (m for help): d Selected partition 1 Command (m for help): n Command action e extended p primary partition (1-4) p Partition number (1-4): 1 First cylinder (1-960, default 1): Using default value 1 Last cylinder or +size or +sizeM or +sizeK (1-960, default 960): Using default value 960 Command (m for help): t Selected partition 1 Hex code (type L to list codes): 6 Changed system type of partition 1 to 6 (FAT16) 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. WARNING: If you have created or modified any DOS 6.x partitions, please see the fdisk manual page for additional information. Syncing disks.
To finish, the partition must be formatted with an actual file system using mkdosfs as the root user. Unmount the device before using mkdosfs. In the below example, /dev/USBPARTITIONNAME might be, for example, /dev/sdb1. Be sure to select the correct partition; formatting destroys all data on it!
$ umount /dev/USBPARTITIONNAME $ /sbin/mkdosfs -F 16 -n usbdisk /dev/USBPARTITIONNAME
If you don't have mkdosfs installed, run "yum install dosfstools" as root.
How to install non-destructively
Skip the repartitioning and formatting step above, and simply continue with the below steps. Please keep in mind you should have at least 1GB free. It is highly recommended to make a backup copy of the data on the USB drive before proceeding in case something goes wrong.
From a Downloaded Image
Download an ISO
You can use BitTorrent or your web browser to download a bootable image, or ISO, which you will install on your USB drive. Quick links:
- Supported releases
- Pre-releases (Rawhide)
You are looking for a file with "Live" in the name, usually of the form "F<version>-Live-<architecture>.iso". For example, "F10-i686-Live.iso" is the Fedora 10 release for 32-bit Pentium Pro and compatible CPUs. "F11-Alpha-x86_64-Live.iso" is the alpha pre-release version of Fedora 11 for 64-bit Intel-compatible CPUs. Be sure to choose the right file for your architecture. (32-bit releases will generally run on 64-bit hardware, but will not be optimized.)
These instructions will also also work for Custom Spins of Fedora Live ISO images, including those you make yourself with Pungi, LiveCD Creator, or Revisor.
Command Line Method - Linux only
In the following examples, replace "/path/to/ISO" with e.g. F10-Live-i686.iso or the full path to the ISO you downloaded, e.g. /tmp/F10-Live-i686.iso.
Replace /dev/USBPARTITIONNAME with the appropriate partition name. For example, /dev/sdb1 in the example above ("Check the size of your USB drive"). Be careful to specify the correct device, or you may lose important data!
Check livecd-tools
Make sure the livecd-tools RPM is installed.
$ rpm -q livecd-tools
You will see the name of the RPM and a version number if it is installed, and no output if it is not installed.
If "livecd-tools" is not installed, install it using yum.
$ su -c "yum install livecd-tools"
Run livecd-iso-to-disk script
Make sure that the USB drive is not mounted before executing the following, and give the root password when prompted.
$ su -c "livecd-iso-to-disk /path/to/ISO /dev/USBPARTITIONNAME" Password: Copying live image to USB stick Updating boot config file Installing boot loader USB stick set up as live image!
Data Persistence
Data persistence means that your files and settings will remain peristent even after you reboot your live system. Persistence is supported from Fedora 9 (beta) onwards. The primary usage of this feature is booting a USB stick with your live image as well as the persistent changes. You can run the following command:
$ livecd-iso-to-disk --overlay-size-mb 512 /path/to/ISO /dev/USBPARTITIONNAME
where 512 is the desired size (in megabytes) of the overlay. The livecd-iso-to-disk shell script won't accept an overlay size value greater than 2047. You can find the livecd-iso-to-disk shell script in the LiveOS directory at the top-level of the CD image. Note that you'll need to have space on your USB stick for the live image plus your overlay plus any other data you want on the stick.
Graphical Method - Windows or Linux
Fedora LiveUSB sticks can be created in Windows and Linux using the liveusb-creator.
For Windows using the following steps:
- Download liveusb-creator from http://fedorahosted.org/liveusb-creator
- Double click 'liveusb-creator'
If you are using Linux, You can use Add/Remove Programs and search for liveusb-creator or on the command line:
$ su -c "yum install liveusb-creator"
To start, run "liveusb-creator" on the command line, or on the GNOME menu, go to "Applications -> System Tools -> liveusb-creator".
If you encounter any issues using this method, please create a ticket against the liveusb-creator.
From a running Live CD/DVD
If you are already running a live CD or DVD and want to convert that into a bootable USB stick, run the following command:
$ livecd-iso-to-disk /dev/live /dev/USBDEVICENAME
How to Boot a Live USB Drive
- Power off the computer.
- Plug the USB drive into a USB port.
- Remove all other portable media, such as CD, DVD, or floppy disks.
- Power on the computer.
- If the computer is configured to automatically boot off of the USB drive, you will see a screen that says "Automatic boot in 10 seconds..." with a countdown.
- If the computer starts to boot off the hard drive, you'll need to manually configure it to boot off the USB drive.
- Wait for a safe point to reboot safely.
- As the machine starts to reboot, watch carefully for instructions on what key to press (usually a function key or Escape) to enter the boot device selection menu, or "BIOS setup". Press and hold that key. If you miss the window of opportunity (often only a few seconds) then reboot and try again.
- Use the BIOS setup menu to put your USB drive first in the boot sequence. It might be listed as a hard drive rather than a removable drive. Each hardware manufacturer has a slightly different method for doing so. Use caution! Your computer could become unbootable or lose functionality if you change any other settings. Though these settings can be put back, you'll need to remember what you changed in order to do so.
- Save the changes, exit, and the computer should boot the Live USB drive.
Errors and Solutions
Partition isn't marked bootable!
If you get the following message, you need to mark the partition bootable.
$ livecd-iso-to-disk Fedora-<release>-Live-i686.iso /dev/sdb1
Partition isn't marked bootable!
You can mark the partition as bootable with
$ /sbin/parted /dev/sdb
(parted) toggle N boot
(parted) quit
Cleaning up to exit...
To mark the partition bootable,
$ parted /dev/sdb GNU Parted 1.8.6 Using /dev/sdb Welcome to GNU Parted! Type 'help' to view a list of commands. (parted) print Model: Imation Flash Drive (scsi) Disk /dev/sdb: 1062MB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 32.3kB 1062MB 1062MB primary fat16 (parted) toggle 1 boot (parted) print Model: Imation Flash Drive (scsi) Disk /dev/sdb: 1062MB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 32.3kB 1062MB 1062MB primary fat16 boot (parted) quit Information: Don't forget to update /etc/fstab, if necessary.
Partition need a filesystem label!
If you get the following message, you need to label the partition.
$ livecd-iso-to-disk Fedora-<release>-Live-i686.iso /dev/sdb1 Need to have a filesystem label or UUID for your USB device Label can be set with /sbin/dosfslabel Cleaning up to exit...
To label the partition.
$ dosfslabel /dev/sdb1 usbdisk
Partition has different physical/logical endings!
If you get the following message, you may need to reformat the flash drive.
$ fdisk -l /dev/sdb Disk /dev/sdb: 2029 MB, 2029518848 bytes 129 heads, 32 sectors/track, 960 cylinders Units = cylinders of 4128 * 512 = 2113536 bytes Device Boot Start End Blocks Id System /dev/sdb1 * 1 961 1981936 6 FAT16 Partition 1 has different physical/logical endings: phys=(967, 128, 32) logical=(960, 31, 32)
MBR appears to be blank!
If your test boot reports a corrupted boot sector, or you get the following message, you need to install MBR.
$ livecd-iso-to-disk Fedora-<release>-Live-i686.iso /dev/sdb1 MBR appears to be blank. You can add an MBR to this device with Cleaning up to exit...
To install MBR,
$ cat /usr/lib/syslinux/mbr.bin > /dev/sdb
SYSLINUX Boot Error!
If you were using the script on previous Red Hat or Fedora Release and getting following error message,
SYSLINUX 3.xx ... EBIOS Load error - Boot error
You may need to upgrade your syslinux to 3.50 or higher from Peter Anvin's SYSLINUX .
Testing Live Image on USB
You can test your Live Image on USB using QEMU as shown in the screenshot on right.
For example, if your USB flash drive is on /dev/sdb1, you could type following command:
$ umount /dev/sdb1 $ qemu -hda /dev/sdb -m 256 -std-vga
See also
Red Hat Magazine | I am Fedora, and so can you!