In revision 55555 in ReactOS was introduced support for USB devices, and after some time it became possible to run the OS from a USB drive. In revision 55714 system was successfully installed and running from Patriot Xporter XT 8Gb USB stick. LiveCD revision 55995 has also been successfully executed from the same device using USB 1.1 OHCI.
Note: To install on USB-HDD is preferable to use Bootcd, and for USB flash drive more preferable option is LiveCD. Differences between installing on USB-HDD or USB flash drive are tiny, but keep in mind that the resource of a USB flash drive is much smaller than that of hard drives. Although ReactOS is not Windows, and intentional resource exhaustion (excessive overwriting of files by the system) should be small or even not present.
For more convenient use or testing of LiveUSB mode, you need to know the following things:
- If you install bootcd, the first phase of installation to a virtual HDD in a virtual machine is much faster than directly to the USB-stick. Therefore later in this article we will consider how to transfer files needed to start the second phase of the installation from a virtual machine to a flash drive/USB-HDD.
- If you will setup ReactOS to a USB-drive and install the MBR/VBR using the installer(without formatting the disk), then it is likely that the system will be unable to boot. And if you want to load from a flash drive not only ReactOS, please refer to the second paragraph of this article.
Installing the system to a USB-drive
Transferring files from VM to USB-drive
First of all, you need to install and run on your computer a virtual machine that supports virtual hard disks format vmdk. These VMs are, for example, VirtualBox and VMWare Player. Then, install ReactOS in a virtual machine, then close the VM. Next, you need to download the command-line utility VMWare Disk Mount Utility Go using command line to the program's folder and execute:
vmware-mount x: path_to_the_vmdk_file
Copy the files from mounted drive to USB-Drive
Disassemble the image using next command:
vmware-mount / d x:
Note: If you want to use other formats of virtual hard disks, then you have to use other similar utilities.
Installing the MBR
- Extract the installer, copy to its folder files from GRUB package.
- Run the GRUB GUI, choose from the disk list your USB flash drive (if you're using Windows, then the number can be found in the Disk Manager). Click to install. Close the window with the message about successful installation.
- Copy file called "grub" to your USB drive.
- If a partition on a flash drive is not active, then make it activeusing any partition management utility.
- Create a menu.lst using next template:
color blue/green yellow/red white/magenta white/magenta timeout 30 default/default title ReactOS root (hd0, 0) kernel/freeldr.sys title ReactLive root (hd0, 0) kernel/loader / setupldr.sys title reboot reboot
Try to boot. If it doesn't work (damn) it could be either due to a bug in the USB driver or because the system regression (or regression of driver). Try to use working revision (check the beginning of the article). If they work then you're dealing with regression. Please report about it to developers. If they also do not work then your USB controller or USB drive is not yet supported. Please report this too as new bug.