Embedded Linux for Developers

Transfering the root filesystem to the target

Having created a skeleton root filesystem in your staging directory, the next task is to transfer it to the target. In the sections that follow, I will describe three possibilities:

• ramdisk: a filesystem image that is loaded into RAM by the bootloader. Ramdisks are easy to create and have no dependencies on mass storage drivers. They can be used in fall-back maintenance mode when the main root filesystem needs updating. They can even be used as the main root filesystem in small embedded devices and, of course, as the early user space in mainstream Linux distributions. A compressed ramdisk uses the minimum amount of storage but still consumes RAM. The contents are volatile so you need another storage ...