| Dracut | |
| Dracut | |
| Author: | Harald Hoyer and others |
| Latest Release Version: | 103 |
| Programming Language: | C, Bash, Rust |
| Operating System: | Linux |
| Platform: | Linux kernel |
| Genre: | initramfs |
| License: | GPLv2+, LGPLv2+ |
Dracut is a set of tools that provide enhanced functionality for automating the Linux boot process. The tool named is used to create a Linux boot image (initramfs) by copying tools and files from an installed system and combining it with the Dracut framework, which is usually found in .
Unlike existing Linux boot images, the Dracut framework attempts to introduce as little hard-coded logic into the initramfs as possible. The initramfs has essentially one purpose: locating and mounting the real root file system so that the boot process can transition to it. This functionality is dependent on device availability. Therefore, instead of having hard-coded scripts to determine device availability and suitability, Dracut's initramfs depends on the Linux device manager (udev) to create symbolic links to device nodes. When the root file system's device node appears, Dracut mounts it as the new root file system. This helps to minimize the time required in initramfs so that things like a 5-second boot are now made possible.
Most of the initramfs generation functionality in Dracut is provided by generator modules that are sourced by the main tool to install specific functionality into the initramfs. They live in the modules subdirectory, and use functionality provided by dracut-functions to do their work.
Currently, dracut supports booting from ext2, ext3, ext4, btrfs, ISO_9660, DM RAID, MD RAID, LVM2, device mapper multipath I/O, dm-crypt, cifs, FCoE, iSCSI, NBD and NFS.
Red Hat is the original author of dracut. Red Hat-derived Linux distributions use dracut for initramfs creation.
Distributions which include dracut, but do not use it by default for initramfs creation:
Most other distributions have made dracut available as an optional package to replace the distribution's default initramfs generator.