Kexec: Difference between revisions

From Alpine Linux
(Added some headings and mention kexec-tools)
m (→‎Installing kexec-tools: added doc package too, you seriously want to read them before using kexec.)
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==Installing kexec-tools==
==Installing kexec-tools==
The userspace tools required to use it can be installed via {{cmd|apk add {{pkg|kexec-tools}}}} 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 {{path|/boot/config-*}} file for {{codeline|CONFIG_KEXEC=y}}
The userspace tools required to use it can be installed via {{cmd|apk add {{pkg|kexec-tools}} {{pkg|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 {{path|/boot/config-*}} file for {{codeline|CONFIG_KEXEC=y}}


==Usage==
==Usage==

Revision as of 18:28, 13 August 2023

Kexec is a system call that enables loading and booting into another kernel. This is useful for fast 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 via:

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

Warning: Running kexec -e does not unmount any filesystems or gracefully shut down any services!


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

See also