USB flash installation media
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This page discusses various methods on how to create a Arch Linux Installer USB drive (also referred to as "flash drive", "USB stick", "USB key", etc) for booting in BIOS and UEFI systems. The result will be a LiveUSB (LiveCD-like) system) that, because of the nature of SquashFS, will discard all changes once the computer shuts down.
If you would like to run a full install of Arch Linux from a USB drive (i.e. with persistent settings), see Installing Arch Linux on a USB key. If you would like to use your bootable Arch Linux USB stick as a rescue USB, see Change Root.
Contents
BIOS and UEFI Bootable USB
It is recommended to create bootable USB with support for both BIOS and UEFI.
In GNU/Linux
This method is slightly more complicated than writing the image directly with dd
, but it does keep the drive usable for data storage. Before you begin, make sure that your USB device is formatted as either FAT32. Also, make sure that you have the latest syslinux package (version 6.02 or newer) installed
- First create a MBR (msdos) partition table with at least one partition, in the USB (it is fine to use an already partitioned USB).
- Mount the ISO image:
# mkdir -p /mnt/{usb,iso} # mount -o loop archlinux-2013.10.01-dual.iso /mnt/iso
- Then create a FAT32 filesystem in the partition on the USB (unmount before, if necessary).
- Mount the newly created FAT32 USB partition, and copy the contents of the installation media to the USB media.
# mount /dev/sdX1 /mnt/usb # cp -a /mnt/iso/* /mnt/usb # sync # umount /mnt/{usb,iso}
ARCH_2013XX
" (with the appropriate release month) or to use an UUID (to re-label it to whatever you like) will get you the infamous "30 seconds" error.Here is how you can replace the archisolabel=ARCH_2013XX
part with your equivalent of archisodevice=/dev/disk/by-uuid/47FA-4071
for both config files at the same time, using a single command:
/dev/sdX1
before running it, else it will become blank (since drive sdX
does not exist).$ sed -i "s|label=ARCH_.*|device=/dev/disk/by-uuid/$(blkid -o value -s UUID /dev/sdX1)|" archiso_sys{32,64}.cfg
- Install Syslinux to the USB by following Syslinux#Manual_install. Overwrite the existing syslinux modules (
*.c32
files) present in the USB (from the ISO) with the ones from the Syslinux pkg to avoid version mismatch related boot failure.
- Mark the USB partition as active by following Syslinux#MBR_partition_table
In Windows
- Do not use any Bootable USB Creator utility for creating the UEFI bootable USB. Do not use dd for Windows to dd the ISO to the USB drive.
- In the below commands X: is assumed to be the USB flash drive in Windows.
- Windows used backward slash
\
as path-separator, so the same is used in the below commands.
- All commands should be run in Windows command prompt as administrator.
-
>
denotes the Windows command prompt.
- Partition and format the USB drive using Rufus USB partitioner. Select partition scheme option as MBR for BIOS and UEFI and File system as FAT32. Uncheck "Create a bootable disk using ISO image" and "Create extended label and icon files" options. Use
- Change the Volume Label of the USB flash drive
X:
to match the LABEL mentioned inarchisolabel=
part in<ISO>\loader\entries\archiso-x86_64.conf
. This step is required for Official ISO (Archiso) but not required for Archboot.
- Extract the ISO (similar to extracting ZIP archive) to the USB flash drive (using 7-Zip.
- Download latest official syslinux 6.xx binaries (zip file) from https://www.kernel.org/pub/linux/utils/boot/syslinux/ and extract it.
- Run the following command (in Windows cmd prompt, as admin)
> cd bios\ > for /r %Y in (*.c32) do copy "%Y" "X:\boot\syslinux\" /y > copy mbr\*.bin X:\boot\syslinux\ /y
- Install Syslinux to the USB by running (use
win64\syslinux64.exe
for x64 Windows):
> cd bios\ > win32\syslinux.exe -d /boot/syslinux -i -a -m X:
- The above step install Syslinux
ldlinux.sys
to the USB partition VBR, sets the partition as active/boot in the MBR partition table and write the MBR boot code to the 1st 400-byte boot code region of the USB.
- The
-d
switch expects path with forward slash path-separator like in *unix systems.
BIOS-only USB using dd
/dev/sdx
.In GNU/Linux
lsblk
./dev/sdx
instead of /dev/sdx1
.# dd bs=4M if=/path/to/archlinux.iso of=/dev/sdx && sync
In Windows
Using Cygwin
Make sure your Cygwin installation contains the dd
package.
dd
for Windows from here. See the next section for more information.Place your image file in your home directory:
C:\cygwin\home\John\
Run cygwin as administrator (required for cygwin to access hardware). To write to your USB drive use the following command:
dd if=image.iso of=\\.\[x]: bs=4M
where image.iso is the path to the iso image file within the cygwin
directory and \\.\[x]
: is your USB flash drive where x is the windows designated letter, e.g. \\.\d:
.
On Cygwin 6.0 find out the correct partition with:
cat /proc/partitions
and write the ISO image with the information from the output. Example:
dd if=image.iso of=/dev/sdb bs=4M
dd for Windows
A GPL licensed dd version for Windows is available at http://www.chrysocome.net/dd. The advantage of this over Cygwin is a smaller download. Use it as shown in instructions for Cygwin above.
To begin, download the latest version of dd for Windows. Once downloaded, extract the archive's contents into Downloads or elsewhere.
Now, launch your command prompt
as an administrator. Next, change directory (cd
) into the Downloads directory.
If your Arch Linux ISO is elsewhere you may need to state the full path, for convenience you may wish to put the Arch Linux ISO into the same folder as the dd executable. The basic format of the command will look like this.
dd if=archlinux-2013-XX-xx-dual.iso of=\\.\x: bs=4m
Simply replace the various null spots (indicated by an "x") with the correct date and correct drive letter.
Here is a complete example.
dd if=ISOs\archlinux-2013.08.01-dual.iso of=\\.\d: bs=4M
In Mac OS X
To be able to use dd
on your USB device on a Mac you have to do some special maneuvers. First of all insert your usb device, OS X will automount it, and in Terminal.app
run:
$ diskutil list
Figure out what your USB device is called with mount
or sudo dmesg | tail
(e.g. /dev/disk1
) and unmount the partitions on the device (i.e., /dev/disk1s1) while keeping the device proper (i.e., /dev/disk1):
$ diskutil unmountDisk /dev/disk1
Now we can continue in accordance with the instructions above (but use bs=8192
if you are using the OS X dd
, the number comes from 1024*8
).
dd if=image.iso of=/dev/disk1 bs=8192
20480+0 records in 20480+0 records out 167772160 bytes transferred in 220.016918 secs (762542 bytes/sec)
It is probably a good idea to eject your drive before physical removal at this point:
$ diskutil eject /dev/disk1
How to restore the USB drive
Because the ISO image is a hybrid which can either be burned to a disc or directly written to a USB drive, it does not include a standard partition table.
After you install Arch Linux and you are done with the USB drive, you should zero out its first 512 bytes (meaning the boot code from the MBR and the non-standard partition table) if you want to restore it to full capacity:
# dd count=1 bs=512 if=/dev/zero of=/dev/sdx && sync
Then create a new partition table (e.g. "msdos") and filesystem (e.g. EXT4, FAT32) using gparted, or from a terminal:
- For EXT2/3/4 (adjust accordingly), it would be:
# cfdisk /dev/sdx # mkfs.ext4 /dev/sdx1 # e2label /dev/sdx1 USB_STICK
- For FAT32, install the dosfstools package and run:
# cfdisk /dev/sdx # mkfs.vfat -F32 /dev/sdx1 # dosfslabel /dev/sdx1 USB_STICK
Other Methods for BIOS systems
In GNU/Linux
Using UNetbootin
UNetbootin can be used on any Linux distribution or Windows to copy your iso to a USB device. However, Unetbootin overwrites syslinux.cfg, so it creates a USB device that does not boot properly. For this reason, Unetbootin is not recommended -- please use dd
or one of the other methods discussed in this topic.
syslinux.cfg
; this must be restored before the USB device will boot properly.Edit syslinux.cfg
:
sysconfig.cfg
default menu.c32 prompt 0 menu title Archlinux Installer timeout 100 label unetbootindefault menu label Archlinux_x86_64 kernel /arch/boot/x86_64/vmlinuz append initrd=/arch/boot/x86_64/archiso.img archisodevice=/dev/sdx1 ../../ label ubnentry0 menu label Archlinux_i686 kernel /arch/boot/i686/vmlinuz append initrd=/arch/boot/i686/archiso.img archisodevice=/dev/sdx1 ../../
In /dev/sdx1
you must replace x with the first free letter after the last letter in use on the system where you are installing Arch Linux (e.g. if you have two hard drives, use c
.). You can make this change during the first phase of boot by pressing Tab
when the menu is shown.
In Windows
Win32 Disk Imager
First, download the program from here. Next, extract the archive and run the executable. Now, select the Arch Linux ISO under the Image File
section and the USB flash device letter (for example, [D:\]) under the Device
section. Finally, click Write
when ready.
.img
extension. However, you can simply change the Files of type
drop-down list to *.*
and continue on to selecting your Arch Linux ISO.USBWriter for Windows
Download the program from http://sourceforge.net/projects/usbwriter/ and run it. Select the arch image file, the target USB stick, and click on the write
button. Now you should be able to boot from the usb stick and install Arch Linux from it.
The Flashnul way
flashnul is an utility to verify the functionality and maintenance of Flash-Memory (USB-Flash, IDE-Flash, SecureDigital, MMC, MemoryStick, SmartMedia, XD, CompactFlash etc).
From a command prompt, invoke flashnul with -p
, and determine which device index is your USB drive, e.g.:
C:\>flashnul -p
Avaible physical drives: Avaible logical disks: C:\ D:\ E:\
When you have determined which device is the correct one, you can write the image to your drive, by invoking flashnul with the device index, -L
, and the path to your image, e.g:
C:\>flashnul E: -L path\to\arch.iso
As long as you are really sure you want to write the data, type yes, then wait a bit for it to write. If you get an access denied error, close any Explorer windows you have open.
If under Vista or Win7, you should open the console as administrator, or else flashnul will fail to open the stick as a block device and will only be able to write via the drive handle windows provides
Loading the installation media from RAM
This method uses Syslinux and a Ramdisk (MEMDISK) to load the entire Arch Linux ISO image into RAM. Since this will be running entirely from system memory, you will need to make sure the system you will be installing this on has an adequate amount. A minimum amount of RAM between 500 MB and 1 GB should suffice for a MEMDISK based, Arch Linux install.
For more information on Arch Linux system requirements as well as those for MEMDISK see the Beginners' Guide and here.
Preparing the USB flash drive
Begin by formatting the USB flash drive as FAT32. Then create the following folders on the newly formatted drive.
-
Boot
-
Boot/ISOs
-
Boot/Settings
-
Copy the needed files to the USB flash drive
Next copy the ISO that you would like to boot to the Boot/ISOs
folder. After that, extract from the following files from the latest release of syslinux from here and copy them into the following folders.
-
./win32/syslinux.exe
to the Desktop or Downloads folder on your system. -
./memdisk/memdisk
to theSettings
folder on your USB flash drive.
Create the configuration file
After copying the needed files, navigate to the USB flash drive, /boot/Settings and create a syslinux.cfg
file.
INITRD
line, be sure to use the name of the ISO file that you copied to your ISOs
folder!/Boot/Settings/syslinux.cfg
DEFAULT arch_iso LABEL arch_iso MENU LABEL Arch Setup LINUX memdisk INITRD /Boot/ISOs/archlinux-2013.08.01-dual.iso APPEND iso
For more information on Syslinux see the Arch Wiki article.
Final steps
Finally, create a *.bat
file where syslinux.exe
is located and run it ("Run as administrator" if you are on Vista or Windows 7):
C:\Documents and Settings\username\Desktop\install.bat
@echo off syslinux.exe -m -a -d /Boot/Settings X:
Universal USB Installer
The Windows tool [1] can be used to quickly create a Live USB media with multiple Installers of many Linux distros. Once created, Installers can be added or removed without reformatting the USB drive.
Troubleshooting
- For the MEMDISK Method, if you get the famous "30 seconds" error trying to boot the i686 version, press the
Tab
key over theBoot Arch Linux (i686)
entry and addvmalloc=448M
at the end. For reference: If your image is bigger than 128MiB and you have a 32-bit OS, then you have to increase the maximum memory usage of vmalloc. [2]
- If you get the "30 seconds" error due to the
/dev/disk/by-label/ARCH_XXXXXX
not mounting, try renaming your USB media toARCH_XXXXXX
(e.g.ARCH_201302
).