Computing Tidbits

This guide shows how to use the open source Virtual Machine (VM) emulator manager, Qemu Manager, to test bootable USB drives in Windows without restarting your computer.  Qemu Manager is a free, simple and fast GUI for the Qemu Emulator that makes creation of Virtual Machines a breeze with easy-to-use wizards.   It’s performance is very good in comparison to other emulators and it comes in installable and portable versions.  Qemu Manager can be downloaded from here.  Qemu Manager version 7.0 was used for this guide.

Installation

For the installable version of Qemu Manager, during the install process, make sure to enable KQemu support for faster performance.

Creating a Virtual Machine

After installation, click on the “+”  (plus) button to create a new VM (Virtual Machine).  The wizard will appear.  Fill in a name for the VM and use None for the operating system.  Use the defaults for the other options and click next.

For Virtual Machine Settings, select Do not use a Virtual Disk Image.  Use the defaults for the other settings.  Click next.

For the advanced settings, use the default setting (Qemu Manager).  Click Finish.  The new VM (BootUSB) will now be visible in the left panel.  If not already plugged in, insert your bootable USB drive.  To reduce chances of selecting the wrong USB drive, make sure you have only one external drive connected to your computer.

With the new VM (BootUSB in this case) selected in the left panel, click the Drives tab.  If the Select Path dialog doesn’t appear, then double-click Hard Disk 0 in the window to make it appear.  In the Select Path dialog, click the Use Physical Disk button.  After the Use Physical Disk dialog opens, select the Open Disk Management button.  Identify your USB drive in the Disk Management window.  In most cases, this will be Disk 1.

Close Disk Management and select your USB drive identified in Disk Management in Use Physical Drive.  Click OK to close the Use Physical Drive dialog.  Your USB will appear in the Select Path dialog, most likely as \\.\PhysicalDrive1 if you have only one hard disk in your PC and one USB drive connected to it.  Click OK to close the Select Path dialog.

Caution: Never attach the Primary hard disk (usually Disk 0) to a Virtual Machine and Boot it!

Back at the main Qemu window and with new VM (BootUSB in this case) selected, click the Drives tab if its not displayed.  Double-click the Boot Order icon in the right hand column to open the Boot Options dialog.  Use the up/down button to move the hard drive to the first position and then click OK to close the dialog.  The setup is complete.  QEMU Manager is now ready to start booting USBs.

Boot USBs in a VM with Qemu Manager

Using Qemu Manager makes testing bootable USBs fast and easy.  To boot a USB drive in the virtual machine, just click the green arrow on the menu.  To close the VM, click the red button.  To toggle control (mouse, keyboard, etc) between the VM window and the computer, press the keyboard’s Control and Alt buttons.  The running application shown in the VM can be manipulated just as if the USB was booted from your computer.  See the documentation for further information or just play around with the buttons on the main menu or the secondary menu which appear just above the VM’s window after it’s launched.

This guide illustrates how to create a multiboot multipartition USB drive using both SYSLINUX and GRUB4DOS.  Because many apps and Linux distros are coded and/or organized in a way intended to operate from dedicated single partition USB drives, they are often notoriously difficult to boot from multiboot USBs.  Thus, while many apps and distros state they are bootable from USBs, often this means they are bootable from single-purpose (and single partition) USB drives, often using UNetbootin or other similar utilities.  Seldom, if ever, are directions provided for installation to an existing multiboot environment, or how to create a multiboot USB in the first place.  To get around this limitation, this guide demonstrates how to setup a USB drive to enable booting several apps and distros from the same partition when possible, or from separate partitions when necessary.

Almost any distro or app can be made to boot from a USB, with some being easier than others.  Sometimes it’s as easy as extracting files and folders from a zip file to the USB.  However, often it’s not always simple; especially when several apps or distros are installed to a partition already cluttered with multiple ISOs, image files, compressed files, system files, configuration files, and various folders.  For the sake of brevity and simplicity, this guide covers selected apps and distros that were tested to work.  By following this guide, it should become apparent how to install other apps and distros not mentioned here.

For this guide, Syslinux is used as the primary boot loader.  GRUB4DOS is used as a secondary bootloader to chainload partitions (Chainloading is a process where control passes from the boot manager to the boot sector) and to boot ISOs and other apps.  In this case, GRUB4DOS is used to pass control (chainload) to Syslinux installed on the other partition’s boot sectors (except for the boot partition, which is directly booted with Syslinux).  The advantage of GRUB4DOS is that currently, it’s MUCH easier to chainload partitions and to boot ISOs using GRUB4DOS than with Syslinux, which is really designed to chainload hard drive partitions rather than USB drive partitions.  Also, some applications (like ISOs) can boot easily with GRUB (or GRUB4DOS), but not always with Syslinux.  Usually, anything that boots with GRUB can also boot with GRUB4DOS, as long as it’s installed to a FAT formatted partition (either FAT16 or FAT32).  When GRUB4DOS and Syslinux are used together however, it greatly expands the booting options for USB drives.  So essentially, as  used here, GRUB4DOS is used to boot ISOs and a few other apps and to control (chainload) Syslinux.  Syslinux is used to boot the active partition and to automatically boot applications installed to the dedicated partitions once control is passed from GRUB4DOS.   It’s important to note that all the applications installed to the dedicated partitions for this guide are already designed to boot with Syslinux, so all that’s necessary is to copy them to a partition in order to be able to use the default menu options provided by the application developers.

This guide is an extension of an earlier one, Booting DSL (Damn Small Linux) from a Multiboot USB Drive, which demonstrated how to add DSL to a working bootable (either single or multiboot) single partition USB drive with Syslinux.  Although creating multiboot USBs can be accomplished in many other ways, after much trial and error, the method here may be one of the easier ways to boot several popular distros and apps from the same partition and/or from multiple partitions for USB drives.  This guide assumes the user has some experience with booting external devices, using partitioning tools, creating Live CDs from ISOs, and has a basic knowledge of Linux, Syslinux, and GRUB4DOS.

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Operating Systems:
Windows 98/XP/Vista/Win7
Parted Magic LiveCD (PM ver 4.7 used for this guide)

Boot-loader and partitioning utilities to download.  Extract to “C:\” or another location of your choice on a Windows computer.
GRUB4DOS (ver 4.4 used for this guide)
Syslinux (ver 3.84 used for this guide, newer versions should also work)

Tested distros and applications used for this guide (download links are provided below in the article body):

DSL (Damn Small Linux) ver 4.4.10-embedded
Parted Magic LiveUSB  ver 4.7
AVG Rescue USB  ver 90-100429
Clonezilla Live (for USB – zip file)  ver 1.2.4-28-486
Puppy Linux  ver 4.31
SuperGrubDisk  ver 1.30
WinME Non-Windows Based Image File W/ImageApp

Hint:  Downloading the above distros and apps to another USB drive, an external HD, or burning them to a CD will ease the task of copying and extracting them to the USB partitions later in this guide.

The configuration files for Syslinux and GRUB4DOS are pre-configured and provided in this guide.  Included are:

• syslinux.cfg
• menu.lst
• submenu.lst
• help.txt

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Here are the steps to follow to create a multiboot, multipartition USB drive:

About Partitioning and Formatting

First, decide on the number and size of the partitions needed to hold everything  to be installed.  Although not covered in this guide, it’s a good idea to have at least a couple of extra partitions and some unallocated space for future expansion and for apps that can only boot from dedicated partitions.  Note that any storage drive device is limited to a maximum of four primary partitions.  To partition a drive with more than four partitions, it’s necessary to create at least one as an extended partition and to create one or more logical ones within that extended partition.  More often than not, it’s possible to boot several apps and distros from the same partition (particularly the boot partition), so sometimes it’s desirable to create a large partition to hold several booted apps and some smaller ones just large enough to hold the apps or distros that require their own partitions.  For simplicity, this guide uses a 2GB USB drive divided into five approximately equal primary partitions (3 primary, 2 logical) of about 400MB each.  The first partition will boot multiple distros and apps, with the other four setup as dedicated partitions (booting a single app or distro).

1. Boot the PC with the Parted Magic LiveCD and use GParted to Partition the USB drive

a.   Connect the USB drive and boot the computer using the Parted Magic LiveCD.  In Parted Magic, start the GParted Partition utility and set it to display the USB drive.  
b.    Use GParted to create three 200MB primary partitions and two 200MB logical partitions in an extended partition of 800MB.  Be sure to format the partitions with FAT16 or FAT32 (It’s recommended to use either FAT16 or FAT32, but do not use both) and set the boot flag for the first partition.  You can also provide identities for the partitions using labels.  See the example GParted image below which uses three primary partitions and one extended partition.  The partitions are labeled as 1, 2, 3, 5 & 6 (4 is the extended partition holding logical partitions 5 & 6.  Partition 4 itself isn’t writable).  Make sure no errors are showing for any partition before moving to the next step.

For step 2, Parted Magic can continue to be used; however, the user may find tasks such as copying, moving, and extracting files somewhat easier using a more familiar Linux distro such as Ubuntu, Puppy, etc.   Parted Magic is suggested for the preceding steps because it contains an up-to-date version of GParted, while other Linux distros often use older versions.   In any case, a non-Windows environment such as Linux must be used to copy the files to all the partitions (except the boot partition) since Windows can only access the bootable partition of  USB drives.

2.  In Parted Magic or another Linux Distro, install Applications and Distributions

Note:  The file ldlinux.sys shown in each of the following screenshots will not exist until steps 3 and 4 are completed.

Partition #2 – DSL (Damn Small Linux)
DSL can be booted two ways: (1) from it’s own partition, or (2) co-existing with other apps and distros on the same partition.  This guide will boot DSL from its own partition (first method), using the default DSL syslinux.cfg file that comes with DSL and setup with multiple booting options.  The other method, installing DSL to co-exist with other apps and distros in a single boot partition (second method) was covered in a previous article: Booting DSL (Damn Small Linux) from a Multiboot USB Drive.

a.  Download DSL Embedded.
b.  Extract DSL Embedded to Partition #2 and copy all the files in the main folder to the root of the partition (erase the original folder afterwards).  The root of the partition should look like this:

Partition #3 – Parted Magic
a.  Download Parted Magic LiveUSB.
b.  Extract to partition #3 and place the two folders, pmagic and boot in the root of the partition (erase the original folder(s) afterwords).  The root of the partition should look like this:

Note: Parted Magic is in it’s own partition to avoid boot conflicts.  Parted Magic, like the other distros and apps installed to dedicated partitions, already comes with a customized syslinux.cfg file.  Parted Magic’s syslinux.cfg file is located in the boot folder (DSL’s and AVG’s are in root, Clonzilla’s is in the syslinux folder).  During the booting process, SYSLINUX automatically searches for the syslinux.cfg file in the following order:

/boot/syslinux/syslinux.cfg
/syslinux/syslinux.cfg
/syslinux.cfg

Note:  The boot order above shows why Parted Magic and many other distros and apps should be placed in their own partitions.  Should another syslinux.cfg file be placed in root, it would be ignored and the Parted Magic syslinux.cfg file would always load since “boot/syslinux/syslinux.cfg” is first in the boot order.  Of course, there are ways to get around this, but the goal of this guide is to create a multiboot USB quickly and easily without modification to the original file contents and structure so that the default boot options of the installed apps and distros are used.

Partition #5 – AVG Rescue CD
a.   Download AVG Rescue (for USB Stick)
b.   Extract to Partition #5.  The root of the partition should look like this:

Partition #6 – Clonezilla
a.  Download Clonezilla Live (for USB – choose the zip file).
b.  Extract to Partition #6.  The root of the partition should look like this:

Partition #1 – Puppy Linux/SuperGrubDisk/WinME Boot Image/Anything else
a.  If you have a working frugal installation of Puppy Linux, copy all of its files to a folder named “puppy” ( min files required for a frugal install of puppy 4.xx are: initrd, pup_xxx.sfs, usbflash, and vmlinuz).
b.  Download SuperGrubDisk ISO (ver 1.30) and place the ISO in a folder named “sgd”.
c.  Download WinME Non-Windows Based Image File W/ImageApp and extract it to its default folder “winmec”.
d.  Try other programs of your own.

Note: Not all ISOs are bootable using GRUB4DOS.  Often, identifying bootable ISOs is a trial and error process to determine whether its possible to do so without modifying the ISO image.  All the ISOs used in this guide were tested to insure they were bootable without modification.  

Click here for the screenshot of Partition #1, or scroll further down this page

3.  In Parted Magic, install Syslinux to the Boot Sectors of the Partitions

Note: another excellent tool to perform steps 3 and 4 is Bootice V0.7.8, which operates in Windows and can access multiple partitions.  It can analyze partitions, format the USB drive, install and restore MBRs and PBRs, and more.  Bootice is fairly easy to use; however, its use is not covered in this guide.

In Parted Magic, open a LXTerminal window and type the following commands to install Syslinux to all partition boot sectors except for the boot partition (partition #1).  Be sure to substitute your USB device in place of sdb(x).  Press ENTER after each of the following commands:

syslinux /dev/sdb2
syslinux /dev/sdb3
syslinux /dev/sdb5
syslinux /dev/sdb6

Exit Parted Magic and boot the computer to Windows for the next steps.

The above commands install Syslinux to the partition boot sectors for the 2nd to 6th partitions (4th excluded), and places the file ldlinux.sys into each partition’s root directory.  However, these commands don’t make the device itself bootable because only the first partition contains the boot flag.  Parted Magic is highly suggested for this step since it usually contains an up-to-date version of Syslinux.

Note: you will not see a response each time the above commands are executed unless there is an error.

4.  In Windows, install Syslinux and the MBR  to the Boot Partition #1 (use Windows for the remainder of Steps)

a.  Exit Parted Magic and reboot the computer to Windows.  Open My Computer to identify the Windows USB drive letter assignment.

Note that for hard drives, Windows can access multiple partitions, but for USB drives, Windows can only access a single bootable partition. 

b. Open a CMD window using Start, Run, enter “CMD” and then hit OK.  In the CMD window, navigate to the win32 folder of the extracted Syslinux folder.  For example, if you extracted Syslinux to C:\syslinux-3.84, then type “C:\syslinux-3.84\win32″ and enter the following command:  “syslinux.exe -sfma x:“  Be sure to substitute “x” with the letter assignment of your USB drive identified in My Computer.

This is an explanation of the above syslinux.exe command from the Syslinux Wiki:
-s     Safe, slow, stupid: uses simpler code that boots better.
-f     Force installing.
-m    MBR: install a bootable MBR sector to the beginning of the drive.
-a     Active: marks the partition used active (=bootable)

(Note: Setting the boot flag was done already in GParted, but it won’t hurt to do it again).

The above command installs a bootable MBR to the first partition of the USB drive, making Syslinux the boot manager for the USB device.

5.  Copy GRUB4DOS to Root of Partition #1

Because Syslinux is the primary bootloader for all the partitions, only two files are needed to boot GRUB4DOS: (1) “grub.exe” and (2) “menu.lst”.

a.  From the extracted GRUB4DOS folder, copy and paste “grub.exe” to Partition #1 .

6.  Create and Configure the syslinux.cfg file and menu.lst Files to the Root of Partition #1

a.   Save the following two files as syslinux.cfg and menu.lst (either open in your browser by clicking them to cut and paste or right click the links and save):

syslinuxcfg (be sure to save as syslinux.cfg)
menulst (be sure to save as menu.lst)

The syslinux.cfg file is used to set the configurable defaults for Syslinux.  The menu.lst file sets the configurable defaults for GRUB4DOS.  Note that the “l” in menu.lst is a small “L” and not the number “1″.  Both files can be edited using a simple text editor.

7.  Add Additional Files to Root of Partition #1

Copy the following files from the syslinux extracted folder to the root of Partition #1:

• vesamenu.c32 from “\com32\menu”  (optional – used only if you want to use a fancier menu in the future)
• reboot.c32 from “\com32\modules”  (required -  adds an option to reboot the computer)
• menu.c32 from “com32\menu”  (required – displays the basic Syslinux menu)
• memdisk from “\memdisk”  (required -  kernel to boot floppy images, disk images and some ISOs)

Optional:
Save the following two files and save them to the root of Partition #1 (either open in your browser by clicking them to cut and paste or right click the links and save):

submenulst (save as submenu.lst)  Provides an extra menu for GRUB4DOS to boot other apps and distros if needed
help (save as help.txt)  Provides a user-defined help menu when F1 is pressed while the Syslinux menu is displayed

Partition #1 should now look like this:

If you followed the above instructions, you should have a working multiboot, multipartition USB.  The Syslinux boot screen should be similar to the screenshots below when you boot the USB drive.  If you receive boot errors when booting to or selecting from the Syslinux menu, try installing Syslinux to the partition boot sectors again (step 3) and reinstalling the Syslinux/MBR to the boot partition (step 4).  Also, use GParted to view the partitions for any errors.  Errors in GParted will display as a yellow triangular symbol for the partition.

Syslinux Boot Menu Screen
GRUB4DOS Boot Menu Screen

If you are having trouble getting DSL (Damn Small Linux) to boot on a multiboot USB with Syslinux, then this guide may help.   After experiencing the same problem and seeing other online complaints about it, I decided to create this guide.

This tutorial describes how to get DSL (Damn Small Linux) to boot from the boot partition of a working multiple boot USB flash drive that uses Syslinux as the boot loader.

Although many related guides on the web describe how to create multiboot USB drives, many are lacking when it comes to DSL because: (1) a different boot loader such as GRUB is used (2) the instructions are for creating dedicated boot USBs using a single app or Linux distro, or (3) they don’t provide enough details specific to DSL.

Rather than create a comprehensive how-to for multiboot flash drives, this guide limits itself to this particular distro, since other guides, including Create a Mulitboot Multipartion USB …, from this site provide instructions for successfully creating multiboot USBs with other Linux distros and applications.

This tutorial applies if the following conditions are met:

1.  You can successfully boot at least one other distro or application on the USB drive with Syslinux (Ver 3.81 was used for this guide)

2.  You want to add DSL to create a multiboot USB drive or you are unable to boot DSL on a USB drive with at least one other distro or application that currently boots with Syslinux

OK.  Now for the instructions:

Download the Embedded Distribution of DSL:

Why use the embedded version?  It’s provided in a zip file, so there is no need to extract and manipulate files from an ISO.   The embedded version also comes with QEMU, which allows DSL to run within Windows and in Linux.  So even if you can’t boot DSL from Syslinux, you can check the integrity of the DSL installation using QEMU by clicking dsl-base.bat in the DSL folder (see next step).  The downside of running DSL with QEMU is that it will be extremely slow, about 5-6 times slower, than when it’s running natively.   The DSL embedded version used for this guide was version 4.4.10.  You can get the embedded version of DSL from here.  The direct download link for the embedded version of DSL used for this guide is dsl-4.4.10-embedded.zip.

Create a Folder for DSL Embedded in the Root of the USB Drive’s Boot Partition and Unzip DSL Embedded to that Folder:

Pick any name you like.  In my case, I made a folder named “DSLEmbedded” on my USB’s root.  The reason for a separate folder is to avoid conflicting files that may already exist on the root for other distros or applications such as syslinux.cfg, knoppix folders, boot.msg, readme.txt and others.  In fact, it’s preferable to put every distro in its own folder when you can, but that’s not always possible without complex folder organization schemes and/or file coding mods.  Because of this, some distros should be in the root by themselves and are thus best installed to their own  partition since they often have complex boot menus, they’re coded to work from root, and/or they have multiple files and folders (making upgrading more complex when installed to a single partition).  However, DSL in a separate folder can coexist with  many other distros using syslinux as the boot-loader – you just need to edit the root’s syslinux.cfg file and experiment to see what can coexist with the least amount of work and conflict.  Currently, I have DSL co-existing in the same partition with SuperGrubDisk, two versions of Puppy Linux, and several Windows apps in ISO format, all booting from the same syslinux menu and almost all of them in separate folders.

Note:  When you unzip DSL embedded, it will place all its files in a folder named “dsl-4.4.10-embedded” by default.  Take everything out of this default folder and put it in your folder (see screen-shot of my folder to the left).  The reason for this is to refer to a basic folder name in the Syslinux.cfg file, preferably one that without dashes, periods, or spaces.

Below are some thumbnail screen-shots showing the organization of the main partition, the Puppy400 folder, and the syslinux.cfg file.  As with all of the screen-shots in this guide, click to enlarge them.  Although outside of the scope of this guide, you can see Grub4Dos (grub.exe and menu.lst) are used to boot ISOs and other apps in multiple partitions which also have Syslinux installed in the boot sector

Partition

Puppy400

Syslinux.cfg

For the Syslinux.cfg file, either click the link in this sentence to open in your browser or right click the link to save it.

Edit the Current syslinux.cfg in the Root drive to Create a Menu Entry for DSL and Save It:

This guide assumes a syslinux.cfg file already exits in the root and is used to boot at least one other distro or application.

Important: Pay particular attention to use of “/” in file paths!  Below is a copy of my entry:

Note:  (1) Unless you used the same name, use the name of your folder in place of “DSLEmbedded” everywhere in the menu label above.  (2) Depending on your needs and/or your system, you may want to change the DSL cheat codes in the APPEND line.  See the DSL Cheat Codes Wiki for more information.

That’s all there is to it.  Reboot your PC or laptop and you should now be able to boot DSL from the Syslinux boot menu!

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If Nothing is Working:

If DSL still doesn’t boot, on another bootable USB drive (with Syslinux as the bootloader), try installing Embedded DSL by itself to the root and not in a separate folder (move everything out of the folder and place it in root).  In other words, and this is important – what was in the default folder (e.g., dsl-4.4.10-embedded or DSLEmbedded) should now be in the root of the partition.  DSL should now boot with the default syslinux.cfg file.  If that works, you are getting close; it’s just a matter of getting the file paths correct for the DSL folder you are going to use.  Next, place DSL in a folder and move the syslinux.cfg file to root and then edit it using the instructions above to get it to boot.  If successful, you can then duplicate those changes to the syslinux.cfg on the other USB drive.   Also, you could just use the 2nd USB drive and add other apps and distros to it.  Add one app or distro at a time then test to see if both boot, then add another distro and test again.

Because there are unlimited combination’s of distros and apps possible, differences in hardware, many multi-booting techniques and other factors, there is no way around some experimentation/trial and error testing to determine what works and what doesn’t.

If you are having trouble making a working multi-boot USB with Syslinux or just want to learn how, below are links to get started.   If you still can’t get DSL to boot after that, then come back and recheck the suggestions again.  Usually, most problems are minor such as using incorrect file paths or file names in the syslinux.cfg file.

Good luck and have fun.

Additional help is available at the following:

Guide for Multi-booting from a USB Drive

Damn Small Linux Wiki: Install to USB from Windows (Method II)

Comments welcome.