dracut.bootup - Linux

Overview

dracut.bootup is a command used during Linux bootup to initialize and configure the system prior to switching to the real root file system. It is essential for loading system drivers, activating logical volume management (LVM), and performing other essential setup tasks.

Syntax

dracut.bootup [options] [target-root]

Options/Flags

  • -M: Mount the target root file system read-only.
  • -N: Skip mounting the target root file system.
  • -e: Pass extra kernel command line options.
  • -p: Probe for and start all available boot-up services.
  • -V: Enable verbose logging.
  • –test: Run in test mode without actually initializing the system.
  • –skip-bootup: Skip the boot-up initialization phase.
  • –selinux-enforce: Enforce SELinux policies during bootup.
  • –selinux-disable: Disable SELinux policies during bootup.

Examples

Mount the root file system and initialize the system:

dracut.bootup

Mount the root file system read-only:

dracut.bootup -M

Skip mounting the root file system:

dracut.bootup -N

Pass extra kernel command line options:

dracut.bootup -e "initrd=partitions"

Common Issues

  • Root file system not found: Ensure that the root file system is accessible and the kernel parameters are correct.
  • Failed to load a module: Check the kernel log for missing dependencies or incompatible versions.
  • LVM activation failed: Verify that the LVM configuration is valid and the necessary devices are present.

Integration

dracut.bootup can be combined with other Linux commands for advanced tasks:

  • Manual bootup initialization: Use dracut.bootup --skip-bootup to enter the initramfs shell and perform manual initialization steps.
  • Creating a custom initramfs: Generate a custom initramfs with specific modules and options using dracut -f custom.img and then use dracut.bootup custom.img to boot from it.

Related Commands

  • initramfs: Initializes the root file system and mounts it as the read-only root.
  • blkid: Lists block devices and their attributes, including their UUIDs and partition table information.
  • bootctl: Manages the EFI boot loader configuration.