Chapter 23. Boot Options

Specifying the Installation Source

inst.repo=

Specifies the installation source - that is, a location where the installation program can find the images and packages it requires. For example:

inst.repo=cdrom

The target must be either:

• an installable tree, which is a directory structure containing the installation program's images, packages and repodata as well as a valid .treeinfo file
• a DVD (a physical disk present in the system's DVD drive)
• an ISO image of the full Red Hat Enterprise Linux installation DVD, placed on a hard drive or a network location accessible from the installation system (requires specifying NFS Server as the installation source)

This option allows for the configuration of different installation methods using different formats. The syntax is described in the table below.

Table 23.1. 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
HMC	inst.repo=hmc
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, replacing X with the version number that you want to use.

Note

In previous releases of Red Hat Enterprise Linux, there were separate options for an installable tree accessible by NFS (the nfs option) and an ISO image located on an NFS source (the nfsiso option). In Red Hat Enterprise Linux 7, the installation program can automatically detect whether the source is an installable tree or a directory containing an ISO image, and the nfsiso option is deprecated.

Disk device names can be set 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 (" ").

inst.stage2=

Specifies the location of the installation program runtime image to be loaded. The syntax is the same as in Specifying the Installation Source. This option expects a path to a directory containing a valid .treeinfo file; the location of the runtime image will be read from this file if found. If a .treeinfo file is not available, Anaconda will try to load the image from LiveOS/squashfs.img.

Use the option multiple times to specify multiple HTTP, HTTPS or FTP sources.

inst.stage2=host1/install.img inst.stage2=host2/install.img	inst.stage2=host3/install.img

Note

By default, the inst.stage2= boot option is used on the installation media and set to a specific label (for example, inst.stage2=hd:LABEL=RHEL7\x20Server.x86_64). If you modify the default label of the file system containing the runtime image, or if you use a customized procedure to boot the installation system, you must ensure this option is set to the correct value.

inst.dd=

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. With the exception of the inst.dd=cdrom option, the device name must always be specified. For example:

inst.dd=/dev/sdb1

Using this option without any parameters (only as inst.dd) will prompt the installation program to ask you for a driver update disk with an interactive menu.

Driver disks can also be loaded from a hard disk drive or a similar device instead of being loaded over the network or from initrd. Follow this procedure:

1. Load the driver disk on a hard disk drive, a USB or any similar device.
2. Set the label, for example, DD, to this device.
3. Start the installation with:

   inst.dd=hd:LABEL=DD:/dd.rpm

   as the boot argument.

Replace DD with a specific label and replace dd.rpm with a specific name. Use anything supported by the inst.repo command instead of LABEL to specify your hard disk drive.

For more information about driver updates during the installation, see Chapter 6, Updating Drivers During Installation on AMD64 and Intel 64 Systems for AMD64 and Intel 64 systems and Chapter 11, Updating Drivers During Installation on IBM Power Systems for IBM Power Systems servers.

Kickstart Boot Options

inst.ks=

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.

Use the option multiple times to specify multiple HTTP, HTTPS and FTP sources. If multiple HTTP, HTTPS and FTP locations are specified, the locations are tried sequentially until one succeeds:

inst.ks=host1/directory/ks.cfg inst.ks=host2/directory/ks.cfg inst.ks=host3/directory/ks.cfg

If you only specify a device and not a path, the installation program will look for the Kickstart file in /ks.cfg on the specified device. If you use this option without specifying a device, the installation program will use the following:

inst.ks=nfs:next-server:/filename

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 23.2. Default Kickstart File Location

DHCP server address	Client address	Kickstart file location
192.168.122.1	192.168.122.100	192.168.122.1:/kickstart/192.168.122.100-kickstart

Additionally, starting with Red Hat Enterprise Linux 7.2, the installer will attempt to load a Kickstart file named ks.cfg from a volume with a label of OEMDRV if present. If your Kickstart file is in this location, you do not need to use the inst.ks= boot option at all.

inst.ks.sendmac

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.

inst.ks.sendsn

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

console=

This kernel option specifies a device to be used as the primary console. For example, to use a console on the first serial port, use console=ttyS0. This option should be used along with 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 installation program afterwards. For example, if you specify console=ttyS0 console=ttyS1, the installation program will use ttyS1.

noshell

Disables access to the root shell during the installation. This is useful with automated (Kickstart) installations - if you use this option, a user can watch the installation progress, but they cannot interfere with it by accessing the root shell by pressing Ctrl+Alt+F2.

inst.lang=

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 27.3.1, “Kickstart Commands and Options”. On systems where the system-config-language package is installed, a list of valid values can also be found in /usr/share/system-config-language/locale-list.

inst.geoloc=

Configures geolocation usage in the installation program. Geolocation is used to preset the language and time zone, and uses the following syntax: inst.geoloc=value

The value parameter can be any of the following:

Table 23.3. Valid Values for the inst.geoloc Option

Disable geolocation	inst.geoloc=0
Use the Fedora GeoIP API	inst.geoloc=provider_fedora_geoip
Use the Hostip.info GeoIP API	inst.geoloc=provider_hostip

If this option is not specified, Anaconda will use provider_fedora_geoip.

inst.keymap=

Specifies the keyboard layout to be used by the installation program. Layout codes are the same as the ones used in the keyboard Kickstart command as described in Section 27.3.1, “Kickstart Commands and Options”.

inst.text

Forces the installation program 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.

inst.cmdline

Forces the installation program 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.

inst.graphical

Forces the installation program to run in graphical mode. This mode is the default.

inst.resolution=

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 800x600.

inst.headless

Specifies that the machine being installed onto does not have any display hardware. In other words, this option prevents the installation program from trying to detect a screen.

inst.xdriver=

Specifies the name of the X driver to be used both during the installation and on the installed system.

inst.usefbx

Tells the installation program to use the frame buffer X driver instead of a hardware-specific driver. This option is equivalent to inst.xdriver=fbdev.

modprobe.blacklist=

Blacklists (completely disables) one or more drivers. Drivers (mods) disabled using this option will be prevented from loading when the installation starts, and after the installation finishes, the installed system will keep these settings. The blacklisted drivers can then be found in the /etc/modprobe.d/ directory.

Use a comma-separated list to disable multiple drivers. For example:

modprobe.blacklist=ahci,firewire_ohci

inst.sshd=0

By default, sshd is only automatically started on IBM Z, and on other architectures, sshd is not started unless the inst.sshd option is used. This option prevents sshd from starting automatically on IBM Z.

inst.sshd

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 Red Hat Enterprise Linux 7 System Administrator's Guide. By default, sshd is only automatically started on IBM Z, and on other architectures, sshd is not started unless the inst.sshd option is used.

Note

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 27.3.1, “Kickstart Commands and Options”.

inst.kdump_addon=

Enables or disables the Kdump configuration screen (add-on) in the installer. This screen is enabled by default; use inst.kdump_addon=off to disable it. Note that disabling the add-on will disable the Kdump screens in both the graphical and text-based interface as well as the %addon com_redhat_kdump Kickstart command.

Network Boot Options

ip=

Configures one or more network interfaces. To configure multiple interfaces, you can use the ip option multiple times - once for each interface. If multiple interfaces are configured, you must also use the option rd.neednet=1, and you must specify a primary boot interface using the bootdev option, described below. Alternatively, you can use the ip option once, and then use Kickstart to set up further interfaces.

This option accepts several different formats. The most common are described in Table 23.4, “Network Interface Configuration Formats”.

Table 23.4. 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:interface: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, host name or other specified parameter. All parameters are optional; only specify the ones you want to override and automatically obtained values will be used for the others.

The method parameter can be any the following:

Table 23.5. Automatic Interface Configuration Methods

Automatic configuration method	Value
DHCP	dhcp
IPv6 DHCP	dhcp6
IPv6 automatic configuration	auto6
iBFT (iSCSI Boot Firmware Table)	ibft

Note

If you use a boot option which requires network access, such as inst.ks=http://host/path, without specifying the ip option, the installation program will use ip=dhcp.

Important

To connect automatically to an iSCSI target, a network device for accessing the target needs to be activated. The recommended way to do so is to use ip=ibft boot option.

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 IPv4 (for example 255.255.255.0) or a prefix for IPv6 (for example 64).

The hostname parameter is the host name of the client system. This parameter is optional.

nameserver=

Specifies the address of the name server. This option can be used multiple times.

rd.neednet=

You must use the option rd.neednet=1 if you use more than one ip option. Alternatively, to set up multiple network interfaces you can use the ip once, and then set up further interfaces using Kickstart.

bootdev=

Specifies the boot interface. This option is mandatory if you use more than one ip option.

ifname=

Assigns a given interface name to a network device with a given MAC address. Can be used multiple times. The syntax is ifname=interface:MAC. For example:

ifname=eth0:01:23:45:67:89:ab

Note

Using the ifname= option is the only supported way to set custom network interface names during installation.

inst.dhcpclass=

Specifies the DHCP vendor class identifier. The dhcpd service will see this value as vendor-class-identifier. The default value is anaconda-$(uname -srm).

inst.waitfornet=

Using the inst.waitfornet=SECONDS boot option causes the installation system to wait for network connectivity before installation. The value given in the SECONDS argument specifies maximum amount of time to wait for network connectivity before timing out and continuing the installation process even if network connectivity is not present.

vlan=

Sets up a Virtual LAN (VLAN) device on a specified interface with a given name. The syntax is vlan=name:interface. For example:

vlan=vlan5:em1

The above will set up a VLAN device named vlan5 on the em1 interface. The name can take the following forms:

Table 23.6. VLAN Device Naming Conventions

Naming scheme	Example
VLAN_PLUS_VID	vlan0005
VLAN_PLUS_VID_NO_PAD	vlan5
DEV_PLUS_VID	em1.0005.
DEV_PLUS_VID_NO_PAD	em1.5.

bond=

Set up a bonding device with the following syntax: bond=name[:slaves][:options]. Replace name with the bonding device name, slaves with a comma-separated list of physical (ethernet) interfaces, and options with a comma-separated list of bonding options. For example:

bond=bond0:em1,em2:mode=active-backup,tx_queues=32,downdelay=5000

For a list of available options, execute the modinfo bonding command.

Using this option without any parameters will assume bond=bond0:eth0,eth1:mode=balance-rr.

team=

Set up a team device with the following syntax: team=master:slaves. Replace master with the name of the master team device and slaves with a comma-separated list of physical (ethernet) devices to be used as slaves in the team device. For example:

team=team0:em1,em2

Advanced Installation Options

inst.kexec

If this option is specified, the installer will use the kexec system call at the end of the installation, instead of performing a reboot. This loads the new system immediately, and bypasses the hardware initialization normally performed by the BIOS or firmware.

Important

Due to the complexities involved with booting systems using kexec, it cannot be explicitly tested and guaranteed to function in every situation.

When kexec is used, device registers (which would normally be cleared during a full system reboot) might stay filled with data, which could potentially create issues for some device drivers.

inst.gpt

Force the installation program to install partition information into a GUID Partition Table (GPT) instead of a Master Boot Record (MBR). This option is meaningless on UEFI-based systems, unless they are in BIOS compatibility mode.

Normally, BIOS-based systems and UEFI-based systems in BIOS compatibility mode will attempt to use the MBR schema for storing partitioning information, unless the disk is 2³² sectors in size or larger. Most commonly, disk sectors are 512 bytes in size, meaning that this is usually equivalent to 2 TiB. Using this option will change this behavior, allowing a GPT to be written to disks smaller than this.

See Section 8.14.1.1, “MBR and GPT Considerations” for more information about GPT and MBR, and Section A.1.4, “GUID Partition Table (GPT)” for more general information about GPT, MBR and disk partitioning in general.

inst.multilib

Configure the system for multilib packages (that is, to allow installing 32-bit packages on a 64-bit AMD64 or Intel 64 system) and install packages specified in this section as such.

Normally, on an AMD64 or 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 or Intel systems (marked as i686) 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 bash which depends on package glibc, the former will be installed in multiple variants, while the latter will only be installed in variants specifically required.

selinux=0

By default, SELinux operates in permissive mode in the installer, and in enforcing mode in the installed system. This option disables the use of SELinux in the installer and the installed system entirely.

Note

The selinux=0 and inst.selinux=0 options are not the same. The selinux=0 option disables the use of SELinux in the installer and the installed system, whereas inst.selinux=0 disables SELinux only in the installer. By default, SELinux is set to operate in permissive mode in the installer, so disabling it has little effect.

inst.nosave=

This option, introduced in Red Hat Enterprise Linux 7.3, controls which Kickstart files and installation logs are saved to the installed system. It can be especially useful to disable saving such data when performing OEM operating system installations, or when generating images using sensitive resources (such as internal repository URLs), as these resources might otherwise be mentioned in kickstart files, or in logs on the image, or both. Possible values for this option are:

input_ks - disables saving of the input Kickstart file (if any).

output_ks - disables saving of the output Kickstart file generated by Anaconda.

all_ks - disables saving of both input and output Kickstart files.

logs - disables saving of all installation logs.

all - disables saving of all Kickstart files and all installation logs.

Multiple values can be combined as a comma separated list, for example: input_ks,logs

inst.zram

This option controls the usage of zRAM swap during the installation. It creates a compressed block device inside the system RAM and uses it for swap space instead of the hard drive. This allows the installer to essentially increase the amount of memory available, which makes the installation faster on systems with low memory.

By default, swap on zRAM is enabled on systems with 2 GiB or less RAM, and disabled on systems with more than 2 GiB of memory. You can use this option to change this behavior - on a system with more than 2 GiB RAM, use inst.zram=1 to enable it, and on systems with 2 GiB or less memory, use inst.zram=0 to disable this feature.

Enabling Remote Access

inst.vnc

Specifies that the installation program'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 installation program. VNC sharing is enabled, so multiple clients can connect to the system at the same time.

Note

A system installed using VNC will start in text mode by default.

inst.vncpassword=

Sets a password on the VNC server used by the installation program. Any VNC client attempting to connecting to the system will have to provide the correct password to gain access. For example, inst.vncpassword=testpwd will set the password to testpwd. The VNC password must be between 6 and 8 characters long.

Note

If you specify an invalid password (one that is too short or too long), you will be prompted to specify a new one by a message from the installation program:

VNC password must be six to eight characters long.
Please enter a new one, or leave blank for no password.

Password:

inst.vncconnect=

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 installation program will use 5900.

Debugging and Troubleshooting

inst.updates=

Specifies the location of the updates.img file to be applied to the installation program runtime. The syntax is the same as in the inst.repo option - see Table 23.1, “Installation Sources” for details. In all formats, if you do not specify a file name but only a directory, the installation program will look for a file named updates.img.

inst.loglevel=

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.

inst.syslog=

Once the installation starts, this option 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 Red Hat Enterprise Linux 7 System Administrator's Guide.

inst.virtiolog=

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.

rd.live.ram

If this option is specified, the stage 2 image will be copied into RAM. When the stage2 image on NFS repository is used, this option may make the installation proceed smoothly, since the installation is sometimes affected by reconfiguring network in an environment built upon the stage 2 image on NFS.

Note that using this option when the stage 2 image is on an NFS server will increase the minimum required memory by the size of the image - roughly 500 MiB.

inst.nokill

A debugging option that prevents anaconda from and rebooting when a fatal error occurs or at the end of the installation process. This allows you to capture installation logs which would be lost upon reboot.