kernel-install
Install kernel and initramfs for bootloaders
TLDR
Add kernel and initramfs images to bootloader partition
Remove kernel from the bootloader partition
Show various paths and parameters that have been configured or auto-detected
SYNOPSIS
kernel-install add VERSION-NR KERNEL-IMAGE-PATH [MACHINE-ID]
kernel-install remove VERSION-NR [MACHINE-ID]
kernel-install inspect [MACHINE-ID]
kernel-install list [MACHINE-ID]
kernel-install [OPTIONS...]
PARAMETERS
--root=PATH
Use alternate filesystem root for operations.
--image=PATH
Operate on mounted OS image tree.
--vroot=DIR
Use directory as virtual root for operations.
-h, --help
Print short help text.
-V, --version
Print version string.
DESCRIPTION
kernel-install is a systemd tool for standardizing the installation, removal, and inspection of Linux kernel images across distributions. It handles placing kernels and initramfs into /boot (or EFI partitions), running hook scripts for tasks like depmod, initramfs generation, and bootloader updates.
Using add VERSION-NR KERNEL-IMAGE-PATH, it creates /boot/VERSION-NR/ with symlinks to vmlinuz, initrd, and config files, executing phased scripts from /usr/lib/kernel/install.d/ (e.g., 50-depmod.install, 99-default.install) and /etc/kernel/install.d/ for customization. Bootloaders like GRUB or systemd-boot are updated via presets.
remove cleans up directories and configs; inspect checks installation status; list enumerates kernels. This ensures consistent kernel management, especially for DKMS modules, custom builds, or package managers triggering installs.
It integrates with dracut, mkinitcpio, or update-initramfs, making it ideal for Arch, Fedora, openSUSE, and Debian derivatives adopting systemd-boot.
CAVEATS
Requires hooks in /usr/lib/kernel/install.d/ for full functionality; not all distros configure out-of-box. Initramfs generation depends on dracut/mkinitcpio presence. Use with booted system or chroot carefully.
HOOK PHASES
Scripts run in order: 00-initrd.install (initramfs), 50-depmod.install (modules), 90-loaderentry.install (bootloader config), 99-default.install. Place custom in /etc/kernel/install.d/.
KERNEL LAYOUT
Installs to /boot/<version>/ with vmlinuz-<version>, initrd.img-<version>, System.map, config symlinks.
HISTORY
Introduced in systemd 243 (Nov 2019) to unify kernel management amid bootloader diversity. Evolved with EFI support, phased hooks, and integration for rpm/deb packages in Fedora, openSUSE.
SEE ALSO
dracut(8), mkinitcpio(8), update-initramfs(8), grub-mkconfig(8), bootctl(1)
