Initramfs

An initial ram filesystem or initramfs is an initial stage used in the loading of Linux operating systems that offloads the job of fetching and mounting the root filesystem from the kernel to userspace tools.

# FEATURES

Loaders:   kernel loader, EFI 
Fetches:   *                  
Loads:     ELF executables    
Size:      10-100MB           

As an archive, an initramfs is a concatenated string of cpio archives, some or all of which may be gzip-compressed. An initramfs can be unpacked using the cpio utility, or inspected at a higher level using lsnitrd. The dracut-cpio and skipcpio utilities are adapted specifically to unpack the cpio archives produced by dracut.

Building the initramfs

The DeBoot project uses a fork of the dracut project to generate initial ram filesystems.