Boot from a removable device
To boot from a CD-ROM or USB device make sure that the computer firmware (BIOS
or UEFI settings) is configured to boot the right device and that the priority
To start SystemRescue, insert the CD or USB in the drive, and power on or
reset your computer, or press a key to select an alternative boot device when it
Current boot options
The following boot options are supported in the latest version:
Press TAB to add additional options on syslinux and press “e” in grub.
- setkmap=xx defines the system to configure the keyboard layout where
corresponds to a keyboard map code. For example
configure the German keyboards layout during the boot process. You can also
set the keyboard layout by running a command such as
from the shell after boot time, and you can run
setkmap with no parameter in
the terminal on a running SystemRescue to get a list of all supported keymaps.
- copytoram causes SystemRescue to be fully loaded into memory. This
corresponds to the
docache option in previous versions. A slower start but
once complete, the system will be more responsive and also it will not require
the original device to run. It means you can actually work on the device where
SystemRescue is installed. This requires 2GB of memory to cache the system.
- cow_spacesize=xx sets the size of the Copy-on-Write area which is stored
in a tmpfs file system in memory. It accepts values such as 512M, 4G and is set
to 25% of the system memory by default.
- checksum will trigger a verification of the squashfs checksum during the
boot so you know if the file has been corrupted. You should use this boot option
if you get unexpected errors when booting SystemRescue.
- nomodeset causes the system to run with a basic display driver in lower
resolution instead of using the most optimal display settings. Use this option
if information is not being displayed properly on the screen.
- findroot: boot a Linux OS installed on disk using the SystemRescue
kernel. This is very useful if you are unable to boot a Linux OS directly using
the normal process. This could be caused by the boot loader being broken for
example. This option allows you to boot your system via SystemRescue so you
can fix the boot loader. This option works by scanning block devices during the
boot process to find filesystems where a Linux operating system is installed
(ie: filesystems which contain a file called
/sbin/init). This includes block
devices which are luks encrypted hence the user will have to provide the
passphrase in order to access these devices. It will then show a list of all
block devices which seems to be Linux root filesystems. The user will then need
to choose the block device from which to boot. This option has been introduced
in SystemRescue version 6.1.4.
- break: stop the boot process before the root filesystem gets mounted. A
shell will be executed from the initramfs. This option allows to run commands
manually in order to troubleshoot issues if SystemRescue cannot boot normally.
- rootpass=password123: Sets the root password of the system running on the
password123. That way you can connect from the network and ssh on
the livecd and authenticate using this password. For security reasons it is
recommended to use the alternative
rootcryptpass option instead of
so the password is not visible as clear text.
- rootcryptpass=xxxx: Sets the root password of the system running on
the livecd to so can can connect to the system remotely via ssh and use the
password to authenticate on the livecd. The password must be encrypted using
a command line such as the following one:
python3 -c 'import crypt; print(crypt.crypt("password123", crypt.mksalt(crypt.METHOD_SHA256)))'
You need to provide the whole encrypted password as printed by the python
command including the
$6$ prefix and the salt. The encrypted password
contains dollars so you should check if your boot loader needs escaping
characters to preserve these special characters. You should check that
/proc/cmdline contains the value that you passed if you have doubts.
- nofirewall stop the iptables and ip6table services which are enabled by
default in order to block incoming connection requests. You need to use this
option if you need to establish connections to the system running SystemRescue
from outside (for example connections to sshd). This option was introduced in
- rootshell=/bin/myshell use an alternative shell such as /bin/zsh instead
of /bin/bash. This option was introduced in SystemRescue-6.1.1.
- archisolabel=xxxx Set the filesystem label where SystemRescue files
reside. In other words the system will try to find SystemRescue files on a
filesystem having the label specified so it is important for it to locate on
which device SystemRescue files are located. This is set to
default since version 7.00 (it used to be
SYSRCDXYZ with versions 6.x)
where XYZ corresponds to the SystemRescue version (eg: the label is
- archisobasedir=xxxx Set the base directory where all SystemRescue files
reside and it is set to
sysresccd by default. In other words the
system will try to find SystemRescue files in a directory named
sysresccd which is located at the root of the filesystem.
- cow_label=xxxx Set the filesystem label where upperdir/workdir files for
overlayfs must be stored. By default this option is not set and changes made on
SystemRescue files are lost after a reboot. In other words you can use a Linux
filesystem to persist all modifications made on SystemRescue when it runs such
as new bookmarks in Firefox, application configuration files, etc. You have to
provide the label of the filesystem that needs to be used to store these
changes. All these changes will be isolated in a directory prefixed by
persistent unless you override this using
- cow_directory=xxxx Name of the directory where to store changes made on
the system. You must have specified a cow device for this change to take effect.
- img_label=xxxx Set the filesystem label where SystemRescue ISO image is
located. This is only used when booting SystemRescue using the loopback option
- img_loop=xxxx Set the path to the SystemRescue ISO image within the
filesystem so the boot process can mount it and find the squashfs filesystem.
This is only used when booting SystemRescue using the loopback option from
- loadsrm=y Load all SRM modules located on the boot device
Please read the archiso documentation
for more advanced boot options and PXE boot in particular.
Options provided for autorun
- ar_source=xxx: place where the autorun are stored. It may be the root directory of a partition (
/dev/sda1), an nfs share (
nfs://192.168.1.1:/path/to/scripts), a samba share (
smb://192.168.1.1/path/to/scripts), or an http directory (
- autoruns=[0-9]: comma separated list of the autorun scripts to be run. For example
autoruns=0,2,7 the autorun scripts
autorun7 are run. Use
autoruns=no to disable all the autorun scripts with a number.
- ar_ignorefail: continue to execute the scripts chain even if a script failed (returned a non-zero status)
- ar_nodel: do not delete the temporary copy of the autorun scripts located in
/var/autorun/tmp after execution
- ar_disable: completely disable autorun, the simple
autorun script will not be executed
- ar_nowait: do not wait for a keypress after the autorun script have been executed.
For more details, please read the page about autorun
Booting from the network via PXE
It is also possible to boot SystemRescue from the network. Since the
installation is not simple, there is a dedicated page to
PXE network booting