Provided by: grml2usb_0.19.2_amd64 
NAME
grml2usb - install Grml ISO(s) on USB device for booting
SYNOPSIS
grml2usb [ options ] <ISO[s]> <device>
Important! The Grml team does not take responsibility for loss of any data!
INTRODUCTION
grml2usb installs Grml on a given partition of your USB device and makes it bootable. It
provides multiboot ISO support, meaning you can specify several Grml ISOs on the command
line at once and select the Grml flavour you would like to boot on the bootprompt then.
Note that the first ISO specified on the grml2usb command line will become the default one
(that’s the one that will boot when just pressing enter on the bootprompt or wait until
the boot timeout matches).
Important
By default a compatible master boot record (MBR) is installed on the device (being for
example /dev/sdX when executing grml2usb grml.iso /dev/sdX1) and syslinux is being
used as default bootloader. Avoid installation of the default MBR using the --skip-mbr
option or if you encounter any problems with the default MBR consider using
--syslinux-mbr instead.
OPTIONS
ISO[s] should be the path to one or multiple grml-ISOs and/or the path to the currently
running live-system (being /run/live/medium).
The device either might be a device name like /dev/sdX1 or a directory. When specifying a
device name the device is mounted automatically. When specifying a directory grml2usb is
assuming that you did set up a bootloader on your own (or don’t need one) and a bootloader
won’t be installed automatically.
The following options are supported:
--bootoptions=...
Use specified bootoptions as default. To use flavour name as a argument for a boot
parameter use %flavour which will be expanded to the flavour name. To add multiple
bootoptions you can specify the option multiple time.
--bootloader-only
Do not copy files but instead just install a bootloader. Note that the boot addons are
copied to /boot/addons at this stage as well. If you want to skip copying the boot
addons consider using the --skip-addons option.
--copy-only
Copy files only but do not install a bootloader.
--dry-run
Avoid executing commands, instead show what would be executed. Warning: please notice
that the ISO has to be mounted anyway, otherwise identifying the Grml flavour would
not be possible.
--fat16
Format specified partition with FAT16. Important: this will destroy any existing data
on the specified partition!
--force
Force any (possible dangerous) actions requiring manual interaction (like --fat16).
--grub
Install grub bootloader instead of (default) syslinux.
--grub-mbr
Install grub into MBR (Master Boot Record) instead of PBR (Partition Boot Record).
Check out the mbr-vs-pbr section in the FAQ of this document for further details.
--help
Display usage information and exit.
--mbr-menu
Install master boot record (MBR) with integrated boot menu: interactively choose the
partition to boot from, with a timeout to load the default partition, or boot from
floppy. When NOT using the --mbr-menu option a MBR with LBA and large disc support but
without an integrated boot menu is installed (so it’s not visible at all but instead
directly jumps to the bootloader - being grub or syslinux). Note: This options is
available only when using the default MBR and won’t have any effect if you’re using
the --syslinux-mbr option.
--quiet
Do not output anything but just errors on console.
--skip-addons
Do not install /boot/addons/ files (like dos, grub, memdisk,...).
--remove-bootoption=...
Remove specified bootoption (could be a regex) from existing boot options. Use
multiple entries for removing different bootoptions at once.
--skip-bootflag
Do not check for presence of boot flag on target device.
--skip-grub-config
Skip generation of grub configuration files. By default the configuration files for
syslinux and grub will be written so you’ve a working configuration file no matter
whether you’re using grub or syslinux as bootloader.
--skip-mbr
Do not touch/install the master boot record (MBR).
--skip-syslinux-config
Skip generation of syslinux configuration files. By default the configuration files
for syslinux and grub will be written so you’ve a working configuration file no matter
whether you’re using grub or syslinux as bootloader.
--skip-usb-check
Skip check to verify whether given device is a removable device. Some USB devices are
known to report wrong information, when using such a device you can skip grml2usb’s
removable device check.
--syslinux
This option is deprecated and is being left only for backwards compatibility reasons.
Syslinux is the default bootloader of grml2usb and therefore the --syslinux option
doesn’t have any effects. If you do not want to use syslinux as bootloader consider
using the --grub option.
--syslinux-mbr
Install syslinux' master boot record (MBR, which is booting from the partition with
the "active" flag set) instead of the default one. If you encounter any problems with
the default MBR you can try using the syslinux MBR instead. If that works for you
please let us know so we can adjust our default MBR accordingly.
-v, --version
Return version and exit.
--verbose
Enable verbose mode.
DEVELOPERS CORNER
Directory layout on USB device
boot/ ->
|-- addons/
| |-- allinone.img [grub - all in one image]
| |-- bsd4grml/ [MirBSD]
| |-- balder10.imz [FreeDOS]
| |-- memdisk [chainloading helper]
| |-- memtest [memtest86+]
|-- release/
| |-- grml/
| | |-- linux26 [Kernel]
| | |-- initrd.gz [initramfs]
| |-- grml64
| | |-- linux26 [Kernel]
| | |-- initrd.gz [initramfs]
| |-- grml-medium
| | |-- linux26 [...]
| | |-- initrd.gz
| |-- grml64-medium
| | |-- linux26
| | |-- initrd.gz
| |-- grml-small
| | |-- linux26
| | |-- initrd.gz
| `-- grml64-small
| |-- linux26
| |-- initrd.gz
|-- grub/
| |-- grml.png [graphical bootsplash background image for grub2]
| |-- grub.cfg [configuration file for grub2]
| |-- menu.lst [configuration file for grub1]
| |-- splash.xpm.gz [splash screen for grub1]
`-- syslinux/
|-- grml.png [graphical bootsplash background image for syslinux]
|-- syslinux.cfg [main configuration file for syslinux]
`-- [....] [several further config files for syslinux]
grml/
|-- grml2usb.txt [not yet implemented]
|-- grml-cheatcodes.txt [list of bootoptions for Grml]
|-- grml-version.txt [file containing information about grml-version]
|-- LICENSE.txt [license information]
|-- md5sums [md5sums of original ISO]
|-- README.txt [informational text]
`-- web/ [browser related files]
|-- index.html
|-- style.css
`-- images/
|-- button.png
|-- favicon.png
|-- linux.jpg
`-- logo.png
live/
|-- grml/
| |-- filesystem.module [module specifying which squashfs should be used for grml]
| `-- grml.squashfs [squashfs file for grml]
|-- grml-medium/
| |-- filesystem.module [module specifying which squashfs should be used for grml-medium]
| `-- grml-medium.squashfs [squashfs file for grml-medium]
|-- grml-small/
| |-- filesystem.module [module specifying which squashfs should be used for grml-medium]
| `-- grml-small.squashfs [squashfs file for grml-small]
`-- ...
Grabbing the source
% git clone git://git.grml.org/grml2usb.git
Developers Debugging Hints
To play with grml2usb you can avoid using a real device via a loopback file setup, like:
# dd if=/dev/zero of=~/loopback bs=1M count=100 # adjust size to your needs
# losetup /dev/loop1 ~/loopback
Then create according partitions either running for example:
# echo -en "n\np\n1\n\n\nt\n6\na\n1\n w\n" | fdisk /dev/loop1
or:
# parted /dev/loop1 -s "mkpart primary fat16 0 -1s mkfs 1 fat16"
Finally create a filesystem and execute grml2usb as needed:
# mkfs.vfat /dev/loop1
# grml2usb --bootloader-only /grml/isos/grml64-small_2018.12.iso /dev/loop1
Performance tracing
# blktrace -d /dev/sdX -o - | blkparse -i -
# grml2usb grml64-full_2018.12.iso /dev/sdX1
TROUBLESHOOTING AND PITFALLS WHEN BOOTING
Here is a list of common error messages from BIOS/bootloader when trying to boot from USB.
Error message ran out of input data. System
halted
Reason Everything OK, except for the
filesystem used on your USB
device. So instead of fat16 you
are using for example fat32.
Fix: use the appropriate
filesystem (fat16 for USB flash
drive usually). The Bootsplash
might be displayed, the kernel
loads but you very soon get the
error message.
Error message Invalid operating system
Reason the partition layout is not ok.
Very probably there’s no primary
partition (/dev/sdX{1..4}) or
none has the flag bootable set.
Error message Boot error.
Reason Some BIOSses offer different
modes for USB booting. The
proper mode to boot a USB stick
is USB-HDD. If that doesn’t work
or is not supported by your
system, you need to format your
USB-Stick as USB-ZIP. To do
this, syslinux contains an
utility called mkdiskimage,
which you can use to re-format
your USB stick in USB-ZIP format
running mkdiskimage -4 /dev/sdX
1 64 32. Please be aware that
this procedure will erase all
data on your stick. After
executing mkdiskimage just
continue installing as usual
(grml2usb ... /dev/sdX4). Note
that this is not going to work
for any device larger than 8 GB,
since mkdiskimage only supports
1024c 256h 63s. For a more
detailed explanation, refer to
/usr/share/doc/syslinux-common/usbkey.txt.
Error message No operating system found.
Reason you forgot to set the boot-flag on the
partition. Or there really isn’t any
operating system at all. :)
Error message kernel-panic: unable to mount root-fs...
Reason Kernel boots but fails to find the root
filesystem. The root= argument in your
kernel commandline is pointing to the
wrong device. Adjust root=..., consider
using root=UUID=....
Error message Could not find kernel image: ...
Reason either a broken isolinux/syslinux version
or a broken BIOS. Check out whether the
vendor provides a BIOS update or if using
bootloader grub instead of
isolinux/syslinux fixes the problem.
FREQUENTLY ASKED QUESTIONS (FAQ)
Where can I get grml2usb?
grml2usb is available as Debian package via the grml-testing Debian repository[1].
If you do not want to (or can’t) use the grml2usb Debian package you can either use the
grml2usb git tree running:
git clone git://git.grml.org/grml2usb.git
cd grml2usb
make -C mbr
sudo ./grml2usb ...
or download the provided http://grml.org/grml2usb/grml2usb.tgz (gpg signed md5 hash[2]).
Download and extract the tarball and execute the provided script install.sh.
Note
It is NOT enough to have just the grml2usb script itself without the according files
provided either via the Debian package, the git tree or the file grml2usb.tgz.
Why can’t I just dd the ISO to a USB device?
Well, you can. :) Starting with Grml 2009.10 the ISOs are dd-able straight out-of-the-box.
Important
Note that ANY existing data on your USB device will be destroyed when using the dd
approach.
This allows you to dd the Grml ISO to your USB device (use for example rawwrite[3] if
you’ve just a Windows system available) running:
% dd if=grml64-full_2018.12.iso of=/dev/sdX
where /dev/sdX is your USB device. Of course this doesn’t provide such a flexible system
like with grml2usb (no multi-ISO setup, no additional default bootoptions,...) but it’s a
nice way to get a working USB boot setup if you don’t have grml2usb available.
What’s the difference between grml2usb and just using dd?
grml2usb does not remove any data from your USB device and does not alter the partition
table at all. grml2usb provides multi-ISO support, support for adding default bootoptions
and selecting the bootloader (syslinux vs. grub) without having to manually touch the ISO
at all.
What’s grml2iso?
grml2iso is a script which uses grml2usb to generate a multiboot ISO out of several Grml
ISOs. See man grml2iso for further details.
Why is there a menu.lst and a grub.cfg inside /boot/grub/?
grml2usb supports grub version 1 (grub1) as well as grub version 2 (grub2). Whereas grub1
uses menu.lst the new version grub2 needs grub.cfg. Providing both files allows grml2usb
to install grub on the target device no matter which grub version is available on the host
where grml2usb is executed on.
grub-install fails with 'The file ../boot/grub/stage1 not read correctly ?!"
Check whether the partition has the right partition type. For example do NOT use FAT16
(partition type 6) when using a ext3 filesystem on the partition but instead use the
correct partition type (83 - Linux) then.
grub-install complains about /sbin/grub-install and/or xfs_freeze?!
The following message:
You shouldn't call /sbin/grub-install. Please call /usr/sbin/grub-install instead!
xfs_freeze: specified file ["/tmp/tmpqaBK6z/boot/grub"] is not on an XFS filesystem
This is "normal". grub-install sends those messages to stderr. To avoid hiding any
possible real error messages grml2usb doesn’t ignore those messages.
grub-install complains about /boot/grub/device.map?!
The following message:
grub-probe: error: Cannot open `/boot/grub/device.map'
This is "normal" (at least with grub1). This isn’t a problem, because the device.map file
will be generated on the target device anyway.
grub-install complains about a unary operator?!
The following message:
'/usr/sbin/grub-install: line 374: [: =: unary operator expected'
This is "normal". Just ignore it. (It usually doesn’t appear on the second invocation on
the same device.)
grub-install fails with grub-probe: error: unknown filesystem?!
The following message:
grub-probe: error: unknown filesystem
Auto-detection of a filesystem module failed.
Please specify the module with the option `--modules' explicitly.
usually means that the device partition table says something else than the filesystem on
the device. For example using FAT16 as filesystem type and using FAT32 as filesystem on
the partition will not work. Either set filesystem type to FAT32 or format the partition
using FAT16. It is essential that device partition table and filesystem use the same
filesystem type.
grub-setup fails after Attempting to install GRUB to a partition instead of the MBR?!
The following message:
grub-setup: warn: Attempting to install GRUB to a partition instead of the MBR. This is a BAD idea.
grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and its use is discouraged.
grub-setup: error: Cannot read `/grub/core.img' correctly
appears when using grub2 versions older than 1.98 as those version introduced a regression
which avoids that grub is being installed into a partition (PBR, Partition Boot Record)
instead of MBR (Master Boot Record).
To work around this issue you can either 1) upgrade to grub versions >=1.98, 2) install
grub into the MBR (Master Boot Record) using the --grub-mbr option of grml2usb or 3)
switch to syslinux as bootmanager (just drop the --grub option).
I’m getting something like Error: /usr/share/grml2usb/grub/splash.xpm.gz can not be read"!?"
Looks like you’ve only the grml2usb script itself available. Please make sure you’ve the
grml2usb Debian package installed. The most resent stable version is available via the
grml-testing Debian repository[1]. If you do not have a Debian system please see section
Where can I get grml2usb? in this FAQ.
Why do I have to use a FAT16/FAT32 filesystem?
Syslinux (currently) does not support any other filesystems besides FAT16/FAT32 (though
that’s a sane default if you want to share your files with other (operating) systems). If
you want to use a different filesystem (like ext2/3) use the bootloader grub instead using
grml2usb’s --grub option.
Note
FAT32 is supported since syslinux version 3.0.
Addons → Hardware Detection Tool freezes
This usually means that the machine you ran grml2usb on had syslinux 3.x installed. The
version of hdt (Hardware detection tool) shipping with Grml 2010.12 and newer requires
syslinux 4.x.
I think I’ve got a really cool idea!
Great! Please check out the TODO file[4]. Feel free to report your wishes to the author.
Patches highly appreciated.
I’ve problems with booting from USB.
Check out Troubleshooting and Pitfalls when booting.
I’ve found a bug!
Please report it to the author. Please provide usage examples and output of your grml2usb
commandline (consider using the "--verbose" option).
USAGE EXAMPLES
# grml2usb /home/grml/grml64-full_2018.12.iso /dev/sdX1
Install specified ISO on device /dev/sdX1.
# grml2usb /home/grml/grml64-full_2018.12.iso /home/grml/grml32-full_2018.12.iso /dev/sdX1
Install specified ISOs on device /dev/sdX1 for multibooting ISOs.
# grml2usb /run/live/medium /dev/sdX1
Install currently running Grml live system on device /dev/sdX1.
# grml2usb /run/live/medium /home/grml/grml64-full_2018.12.iso /dev/sdX1
Install currently running Grml live system and the specified ISO on device /dev/sdX1 for
multibooting.
# grml2usb --fat16 /home/grml/grml64-full_2018.12.iso /dev/sdX1
Install specified ISO on device /dev/sdX1 and format partition /dev/sdX1 with FAT16
filesystem.
# grml2usb --grub --grub-mbr /home/grml/grml64-full_2018.12.iso /dev/sdX1
Install specified ISO on device /dev/sdX1 and use grub as bootloader (instead of syslinux
being the default) and install a master boot record (MBR) to the MBR of /dev/sdX.
# grml2usb --bootoptions="lang=de ssh=mysecret" grml64-full_2018.12.iso /dev/sdX1
# grml2usb --bootoptions="lang=de" --bootoptions="ssh=mysecret" grml64-full_2018.12.iso /dev/sdX1
Install specified ISO on device /dev/sdX1 and use "lang=de ssh=mysecret" as default
bootoptions.
# grml2usb --remove-bootoption="vga=791" --remove-bootoption="nomce" grml64-full_2018.12.iso /dev/sdX1
Install specified ISO on device /dev/sdX1 remove vga=791 and nomce from existing
bootoptions.
# grml2usb --bootoptions="persistent-path=%flavour_name" grml64-small_2018.12.iso grml32-small_2018.12.iso /dev/sdX1
Install specified ISOs on device /dev/sdx and add parameter persistent-path to every menu
entry. %flavour_name will be expanded to the flavour of the specific iso, e.g. grml64 and
grml.
ONLINE RESOURCES
Check out the grml2usb webpage[5] and the grml2usb git repository[6].
BUGS
Please report feedback, bugreports and wishes to the author.
AUTHOR
Michael Prokop <mika@grml.org[7]>
NOTES
1. the grml-testing Debian repository
http://deb.grml.org/
2. gpg signed md5 hash
http://grml.org/grml2usb/grml2usb.tgz.md5.asc
3. rawwrite
http://www.chrysocome.net/rawwrite
4. the TODO file
http://git.grml.org/?p=grml2usb.git;a=blob;f=TODO;hb=HEAD
5. grml2usb webpage
http://grml.org/grml2usb/
6. grml2usb git repository
http://git.grml.org/?p=grml2usb.git
7. mika@grml.org
mailto:mika@grml.org
02/20/2023 GRML2USB(8)