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Chapter 11. Boot Options

11.1. Configuring the Installation System at the Boot Menu
11.2. Enhancing Hardware Support
11.2.1. Overriding Automatic Hardware Detection
11.3. Using the Maintenance Boot Modes
11.3.1. Loading the Memory (RAM) Testing Mode
11.3.2. Verifying Boot Media
11.3.3. Booting Your Computer in Rescue Mode
The Fedora installation system includes a range of functions and options for administrators. To use boot options, append them to the boot command line. To access the command line on a system that displays a graphical boot screen, press the Tab key while one of the boot options on the screen is highlighted, or press the Esc key at any point in the boot menu. Multiple options added to the boot line need to be separated by a single space.
Throughout this chapter, some options are presented ending an "equals" sign ('='). These options require a value to be specified. For example, the inst.vncpassword= option must also contain a password — for example, inst.vncpassword=testpasswd. Other options are presented without the = sign; these options are booleans. This means that you either use them without specifying a value, or you can append either =1 or =0 to enable or disable them, respectively. For example, the option is the same as, and using is exactly the same as not using the option at all.


The Fedora installation can either boot with rescue mode, or load the installation system. For more information on rescue mode, see Section 11.3.3, “Booting Your Computer in Rescue Mode”.

11.1. Configuring the Installation System at the Boot Menu

The boot: prompt always expects the first option to specify the image file to be loaded. When using custom boot options with the Anaconda installer, the linux option will come first in most cases. A valid command in the boot prompt will therefore almost always look like the following:
boot:linux options
This only applies to the actual boot prompt, which is accessed by pressing the Esc key in the boot menu. If you are only modifying an existing set of options (accessed by highliting a choice in the boot menu and pressing the Tab key), the linux option is not displayed, but it is implied. A valid set of boot options will then be:
In addition to the options described in this chapter, the boot prompt also accepts valid dracut kernel options. A list of these options is available as the dracut.cmdline(7) man page.


Boot options specific to the installer always start with inst. in this guide. Currently, this prefix is optional, for example, inst.resolution= will work exactly the same as resolution=. However, it is expected that Anaconda will require the inst. prefix in future releases.
Specifying the Installation Source
Specifies the installation source — that is, a location where the installer can find the images and packages it needs. For example:
The target must be either:
  • an installable tree, which is a directory structure containing the installer's images, packages and repodata as well as a valid .treeinfo file
  • a mounted DVD (either a physical DVD in a DVD drive or a loopback-mounted image)
This option allows for the configuration of different installation methods using different formats. The syntax is described in the table below.
Table 11.1. Installation Sources
Installation source Option format
Any CD/DVD drive inst.repo=cdrom
Specific CD/DVD drive inst.repo=cdrom:device
Hard Drive inst.repo=hd:device/path
HTTP Server inst.repo=http://host/path
HTTPS Server inst.repo=https://host/path
FTP Server inst.repo=ftp://username:password@host/path
NFS Server inst.repo=nfs:[options:]server:/path [a]
[a] This option uses NFS protocol version 3 by default. To use a different version, add +nfsvers=X to options.

Disk device names may be specified using the following formats:
  • Kernel device name, for example /dev/sda1 or sdb2
  • File system label, for example LABEL=Flash or LABEL=RHEL7
  • File system UUID, for example UUID=8176c7bf-04ff-403a-a832-9557f94e61db
Non-alphanumeric characters must be represented as \xNN, where NN is the hexadecimal representation of the character. For example, \x20 is a white space (' ').
Specifies the location of the installer runtime image to be loaded. The syntax is the same as in Specifying the Installation Source. This option will ignore everything except for the image itself, it is not possible to use it to specify the location of packages.
If you need to perform a driver update during the installation, use the inst.dd= option. It can be used multiple times. The location of a driver rpm package can be specified using any of the formats detailed in Specifying the Installation Source. For example:
Kickstart Boot Options
Gives the location of a Kickstart file to be used to automate the installation. Locations can be specified using any of the formats valid for inst.repo. See Specifying the Installation Source for details.
If you only specify a device and not a path, Anaconda will look for the Kickstart file in /ks.cfg on the specified device. If you use this option without specifying a device, the installer will use the following:
In the above example, next-server is the DHCP next-server option or the IP address of the DHCP server itself, and filename is the DHCP filename option, or /kickstart/. If the given file name ends with the / character, ip-kickstart is appended. For example:
Table 11.2. Default Kickstart File Location
DHCP server address Client address Kickstart file location

Adds headers to outgoing HTTP requests with the MAC addresses of all network interfaces. For example:
X-RHN-Provisioning-MAC-0: eth0 01:23:45:67:89:ab
This can be useful when using inst.ks=http to provision systems.
Adds a header to outgoing HTTP requests. This header will contain the system's serial number, read from /sys/class/dmi/id/product_serial. The header has the following syntax:
X-System-Serial-Number: R8VA23D
Console, Environment and Display Options
This kernel option specifies a device to be used as the primary console. For example, if you want to use a console on the first serial port, use console=ttyS0. Implies the inst.text option.
You can use this option multiple times. In that case, the boot message will be displayed on all specified consoles, but only the last one will be used by the installer afterwards. For example, if you specify console=ttyS0 console=ttyS1, the installer will use ttyS1.
Sets the language to be used during the installation. Language codes are the same as the ones used in the lang Kickstart command as described in Section 15.4, “Kickstart Options”. On systems where the system-config-language package is installed, a list of valid values can also be find in /usr/share/system-config-language/locale-list.
Configures geolocation usage in the installer. Geolocation is used to pre-set the language and time zone. This option takes the following format:
The value parameter can be any of the following:
Table 11.3. Valid Values for the inst.geoloc Option
Disable geolocation inst.geoloc=0
Use the Fedora GeoIP API inst.geoloc=provider_fedora_geoip
Use the GeoIP API inst.geoloc=provider_hostip

If this option is not specified, Anaconda will use provider_fedora_geoip.
Specifies the keyboard layout to be used by the installer. Layout codes are the same as the ones used in the keyboard Kickstart command as described in Section 15.4, “Kickstart Options”.
Forces the installer to run in text mode instead of graphical mode. The text user interface is limited, for example, it does not allow you to modify the partition layout or set up LVM. When installing a system on a machine with a limited graphical capabilities, it is recommended to use VNC as described in Enabling Remote Access.
Forces the installer to run in command line mode. This mode does not allow any interaction, all options must be specified in a Kickstart file or on the command line.
Forces the installer to run in graphical mode. This mode is the default.
Specifies the screen resolution in graphical mode. The format is NxM, where N is the screen width and M is the screen height (in pixels). The lowest supported resolution is 640x480.
Specifies that the machine being installed onto does not have any display hardware. In other words, this options prevents the installer from trying to detect a screen.
Specifies the name of the X driver to be used both during the installation and on the installed system.
Tells the installer to use the frame buffer X driver instead of a hardware-specific driver. This option is equivalent to inst.xdriver=fbdev.
Starts the sshd service during the installation, which allows you to connect to the system during the installation using SSH and monitor its progress. For more information on SSH, see the ssh(1) man page and the corresponding chapter in the Fedora System Administrator's Guide.


During the installation, the root account has no password by default. You can set a root password to be used during the installation with the sshpw Kickstart command as described in Section 15.4, “Kickstart Options”.
Network Boot Options
Initial network initialization is handled by dracut. This section only lists some of the more commonly used options; for a complete list, see the dracut.cmdline(7) man page.
Configures one or more network interfaces. To configure multiple interfaces, use the ip option multiple times — once for each interface. If multiple interfaces are configured, you must specify a primary boot interface using the bootdev option described below.
This option accepts several different formats. The most common are described in Table 11.4, “Network Interface Configuration Formats”.
Table 11.4. Network Interface Configuration Formats
Configuration Method Option format
Automatic configuration of any interface ip=method
Automatic configuration of a specific interface ip=interface:method
Static configuration ip=ip::gateway:netmask:hostname:interface:none
Automatic configuration of a specific interface with an override [a] ip=ip::gateway:netmask:hostname:method:mtu
[a] Brings up the specified interface using the specified method of automatic configuration, such as dhcp, but overrides the automatically obtained IP address, gateway, netmask, hostname or other specified parameter. All parameters are optional; only specify the ones you wish to override and automatically obtained values will be used for the others.

The method parameter can be any the following:
Table 11.5. Automatic Interface Configuration Methods
Automatic configuration method Value
DHCP dhcp
IPv6 DHCP dhcp6
IPv6 automatic configuration auto6
iBFT (iSCSI Boot Firmware Table) ibft


If you used a boot option which requires network access, such as inst.ks=http://host:/path and you did not specify the ip option, the installer will use ip=dhcp.
In the above tables, the ip parameter specifies the client's IP address. IPv6 addresses can be specified by putting them in square brackets, for example, [2001:DB8::1].
The gateway parameter is the default gateway. IPv6 addresses are accepted here as well.
The netmask parameter is the netmask to be used. This can either be a full netmask (for example or a prefix (for example 64).
The hostname parameter is the host name of the client system. This parameter is optional.
Specifies the address of the nameserver you want to use. This option can be used multiple times.
Specifies the boot interface. This option is mandatory if you used more than one ip option.
Assigns a given interface name to a network device with a given MAC address. Can be used multiple times. The syntax ifname=interface:MAC. For example:
Specifies the DHCP class vendor identifier. The dhcpd service will see this value as vendor-class-identifier. The default value is anaconda-$(uname -srm).
Advanced Installation Options
Configure the system for multilib packages (that is, to allow installing 32-bit packages on a 64-bit x86 system) and install packages specified in this section as such.
Normaly, on an AMD64/Intel 64 system, only packages for this architecture (marked as x86_64) and packages for all architectures (marked as noarch would be installed. When you use this option, packages for 32-bit AMD/Intel systems (marked as i586, i686, etc.) will be automatically installed as well if available.
This only applies to packages directly specified in the %packages section. If a package is only installed as a dependency, only the exact specified dependency will be installed. For example, if you are installing package foo which depends on package bar, the former will be installed in multiple variants, while the latter will only be installed in variants specifically required.
Install partition information into a GPT (GUID Partition Table) instead of MBR (Master Boot Record).
Enabling Remote Access
Specifies that the installer's graphical interface should be run in a VNC session. If you specify this option, you will need to connect to the system using a VNC client application to be able to interact with the installer. VNC sharing is enabled, so multiple clients can connect to the system at the same time.


A system installed using VNC will start in text mode by default.
Sets a password on the VNC server used by the installer. Any VNC client attempting to connecting to the system will have to provide the correct password to gain access. For example, inst.vncpassword=testpasswd will set the password to testpasswd.
Connect to a listening VNC client at a specified host and port once the installation starts. The correct syntax is inst.vncconnect=host:port, where host is the address to the VNC client's host, and port specifies which port to use. The port parameter is optional, if you do not specify one, the installer will use 5900.
Debugging and Troubleshooting
Specifies the location of the updates.img file to be applied to the installer runtime. The syntax is the same as in the inst.repo option — see Table 11.1, “Installation Sources” for details. In all formats, if you do not specify a file name but only a directory, the installer will look for a file named updates.img.
Specifies the minimum level for messages to be logged on a terminal. This only concerns terminal logging; log files will always contain messages of all levels.
Possible values for this option from the lowest to highest level are: debug, info, warning, error and critical. The default value is info, which means that by default, the logging terminal will display messages ranging from info to critical.
Once the installation starts, this options sends log messages to the syslog process on the specified host. The remote syslog process must be configured to accept incoming connections. For information on how to configure a syslog service to accept incoming connections, see the Fedora System Administrator's Guide.
Specifies a virtio port (a character device at /dev/virtio-ports/name) to be used for forwarding logs. The default value is org.fedoraproject.anaconda.log.0; if this port is present, it will be used.