Description: OverlayFS is a union filesystem that allows one filesystem to be overlaid on another, creating a unified view of both. This approach is particularly useful in environments where efficient file and directory management is required, as it allows combining a read-only filesystem with a read-write one. OverlayFS is based on the idea that changes made in the upper filesystem do not affect the lower filesystem, making it easy to create temporary or testing environments without altering the original data. This filesystem is lightweight and efficient, making it ideal for use in various environments that require rapid file implementation and management. Additionally, OverlayFS is compatible with various Linux distributions, making it a versatile option for developers and system administrators seeking a flexible solution for file management.
History: OverlayFS was introduced in the Linux kernel in 2013 as a solution to the need for a more efficient and user-friendly union filesystem than those existing at the time, such as UnionFS and aufs. Its development focused on improving performance and simplicity, allowing users to create file layers more effectively. Since its inclusion in the kernel, OverlayFS has been widely adopted in various Linux distributions and has become an essential component in container technologies.
Uses: OverlayFS is primarily used in container environments, where efficient file management and the ability to create isolated environments are required. It is also employed in general operating systems that need to implement temporary changes without affecting the base filesystem. Additionally, it is useful in development and testing scenarios, where developers can experiment without risking damage to original data.
Examples: A practical example of OverlayFS is its use in container technologies, where it allows creating container images that can be modified without altering the base image. Another case is in systems that utilize live environments, where changes can be made to the filesystem without affecting the original installation medium.
