systemd kernel-install 8 kernel-install Add and remove kernel and initramfs images to and from /boot kernel-install COMMAND OPTIONS KERNEL-VERSION KERNEL-IMAGE INITRD-FILE kernel-install is used to install and remove kernel and initramfs images to and from the boot loader partition, referred to as $BOOT here. It will usually be one of /boot/, /efi/, or /boot/efi/, see below. kernel-install will execute the files located in the directory /usr/lib/kernel/install.d/ and the local administration directory /etc/kernel/install.d/. All files are collectively sorted and executed in lexical order, regardless of the directory in which they live. However, files with identical filenames replace each other. Files in /etc/kernel/install.d/ take precedence over files with the same name in /usr/lib/kernel/install.d/. This can be used to override a system-supplied executables with a local file if needed; a symbolic link in /etc/kernel/install.d/ with the same name as an executable in /usr/lib/kernel/install.d/, pointing to /dev/null, disables the executable entirely. Executables must have the extension .install; other extensions are ignored. An executable should return 0 on success. It may also return 77 to cause the whole operation to terminate (executables later in lexical order will be skipped). The following commands are understood: add KERNEL-VERSION KERNEL-IMAGE [INITRD-FILE ...] This command expects a kernel version string and a path to a kernel image file as arguments. kernel-install calls the executables from /usr/lib/kernel/install.d/*.install and /etc/kernel/install.d/*.install with the following arguments: add KERNEL-VERSION $BOOT/MACHINE-ID/KERNEL-VERSION/ KERNEL-IMAGE [INITRD-FILE ...] Two default plugins execute the following operations in this case: kernel-install creates $BOOT/MACHINE-ID/KERNEL-VERSION, if enabled (see $KERNEL_INSTALL_LAYOUT=). 50-depmod.install runs depmod8 for the KERNEL-VERSION. 90-loaderentry.install copies KERNEL-IMAGE to $BOOT/MACHINE-ID/KERNEL-VERSION/linux. If INITRD-FILEs are provided, it also copies them to $BOOT/MACHINE-ID/KERNEL_VERSION/INITRD-FILE. It also creates a boot loader entry according to the Boot Loader Specification in $BOOT/loader/entries/MACHINE-ID-KERNEL-VERSION.conf. The title of the entry is the PRETTY_NAME parameter specified in /etc/os-release or /usr/lib/os-release (if the former is missing), or "Linux KERNEL-VERSION", if unset. If $KERNEL_INSTALL_LAYOUT= is not "bls", this plugin does nothing. remove KERNEL-VERSION This command expects a kernel version string as single argument. This calls executables from /usr/lib/kernel/install.d/*.install and /etc/kernel/install.d/*.install with the following arguments: remove KERNEL-VERSION $BOOT/MACHINE-ID/KERNEL-VERSION/ Afterwards, kernel-install removes the directory $BOOT/MACHINE-ID/KERNEL-VERSION/ and its contents. Two default plugins execute the following operations in this case: 50-depmod.install removes the files generated by depmod for this kernel again. 90-loaderentry.install removes the file $BOOT/loader/entries/MACHINE-ID-KERNEL-VERSION.conf. kernel-install removes $BOOT/MACHINE-ID/KERNEL-VERSION, if enabled (see $KERNEL_INSTALL_LAYOUT=). The partition where the kernels and Boot Loader Specification snippets are located is called $BOOT. kernel-install determines the location of this partition by checking /efi/, /boot/, and /boot/efi/ in turn. The first location where $BOOT/loader/entries/ or $BOOT/$MACHINE_ID/ exists is used. The following options are understood: -v --verbose Output additional information about operations being performed. If --verbose is used, $KERNEL_INSTALL_VERBOSE=1 will be set for the plugins. They may output additional logs in this case. If MACHINE_ID= is set and not empty, it will be used as MACHINE-ID, overriding any automatic detection attempts. The value must be a valid machine ID (32 hexadecimal characters). KERNEL_INSTALL_MACHINE_ID= is set for the plugins to the desired MACHINE-ID – either 32 hexadecimal characters or the special value Default. KERNEL_INSTALL_BOOT_ROOT= is set for the plugins to the root directory (mount point, usually) of the hierarchy where boot-loader entries, kernel images, and associated resources should be placed. Can be overridden by setting BOOT_ROOT=. KERNEL_INSTALL_LAYOUT=bls|other|... specifies the installation layout. Defaults to bls if $BOOT/MACHINE-ID exists, or other otherwise. Additional layout names may be defined by convention. If a plugin uses a special layout, it's encouraged to declare its own layout name and configure layout= in install.conf upon initial installation. bls Standard Boot Loader Specification layout, compatible with systemd-boot7: entries in $BOOT/loader/entries/MACHINE-ID-KERNEL-VERSION[+TRIES].conf, kernel and initrds under $BOOT/MACHINE-ID/KERNEL-VERSION/ Provided by 90-loaderentry.install. other Some other layout not understood natively by kernel-install. If every executable returns 0 or 77, 0 is returned, and a non-zero failure code otherwise. /usr/lib/kernel/install.d/*.install /etc/kernel/install.d/*.install Drop-in files which are executed by kernel-install. /usr/lib/kernel/cmdline /etc/kernel/cmdline /proc/cmdline Read by 90-loaderentry.install. The content of the file /etc/kernel/cmdline specifies the kernel command line to use. If that file does not exist, /usr/lib/kernel/cmdline is used. If that also does not exist, /proc/cmdline is used. /etc/kernel/tries Read by 90-loaderentry.install. If this file exists a numeric value is read from it and the naming of the generated entry file is slightly altered to include it as $BOOT/loader/entries/MACHINE-ID-KERNEL-VERSION+TRIES.conf. This is useful for boot loaders such as systemd-boot7 which implement boot attempt counting with a counter embedded in the entry file name. /etc/machine-id The content of this file specifies the machine identification MACHINE-ID. If /etc/machine-id cannot be read or is temporary (backed by a file on tmpfs), kernel-install will use Default instead. /etc/machine-info If this file contains the KERNEL_INSTALL_MACHINE_ID variable, kernel-install will use it as MACHINE-ID instead of the contents of /etc/machine-id. If the variable is not found in /etc/machine-info, kernel-install will try to save the machine ID it uses to install to $BOOT to this file. /etc/os-release /usr/lib/os-release Read by 90-loaderentry.install. If available, PRETTY_NAME is read from these files and used as the title of the boot menu entry. Otherwise, Linux KERNEL-VERSION will be used. /usr/lib/kernel/install.conf /etc/kernel/install.conf Configuration options for kernel-install, as a series of KEY=VALUE assignments, compatible with shell syntax. See the Environment variables section for supported keys. machine-id5, os-release5, depmod8, systemd-boot7, Boot Loader Specification