Kexec

Kexec is a system call that enables loading and booting into another kernel. This is useful for faster reboots that skip the BIOS or UEFI initialisation process.

Installing kexec-tools

The userspace tools required to use it can be installed via

apk add kexec-tools kexec-tools-doc

The tools are not available on all flavors of Alpine, additionally not all kernels are compiled with the kexec syscall enabled. You will most likely want to check your /boot/config-* file for CONFIG_KEXEC=y

Usage

On a typical Alpine setup, it can be used manually via:

# kexec -l /boot/vmlinuz-edge --initrd \ /boot/initramfs-edge --reuse-cmdline \ && openrc shutdown # kexec -e

Note: if the above is being used in a script and the machine is expected to reboot in the event of a kexec failure, append || reboot to the last line

There are no Alpine-specific considerations for Kexec. Please review the man page and existing references below for more details. This page is deliberately kept short in order to avoid duplicating existing documentation.

See also

• Gentoo Wiki: Kexec
• ArchWiki: Kexec