# Linux Kernel Module Cheat

### 8.1. initrd in desktop distros

Most modern desktop distributions have an initrd in their root disk to do early setup.

The rationale for this is described at: https://en.wikipedia.org/wiki/Initial_ramdisk

One obvious use case is having an encrypted root filesystem: you keep the initrd in an unencrypted partition, and then setup decryption from there.

I think GRUB then knows read common disk formats, and then loads that initrd to memory with a `/boot/grub/grub.cfg` directive of type:

    initrd /initrd.img-4.4.0-108-generic

Related: https://stackoverflow.com/questions/6405083/initrd-and-booting-the-linux-kernel