Filesystem Recovery Course

In this course, we cover topics related to various aspects of filesystem recovery.

This section is currently being expanded, we are planning to cover topics from filesystem basics to specifics of most widely used filesystems.

Also, you may find helpful to have at hand a textbook Logical Data Recovery, which formed the basis of this course.

Lesson 1 - File Storage Basics

From this lesson, you learn about the basics of storing data: what filesystem is, what units a filesystem operates with, where different filesystems store their metadata. Additionally, you learn about fragmentation, sparse files, compressed files, deduplication, journaling, checksums, and copy-on-write.


Lesson 2 - File Metadata

From this lesson, you learn about file metadata: what metadata includes, and how it is stored on different filesystems. Additionally, you learn how files are deleted on filesystems using tables to store metadata and on filesystems using b-trees for metadata.


Lesson 3 - FAT Filesystem

From this lesson, you learn about FAT filesystem: the variety of FAT versions, main metadata structures, on-disk FAT volume layout, and the differences between old and new format of FAT directory entry. Additionally, we discuss what changes in directory entry and FAT table are done when a file is deleted on FAT filesystem.


Lesson X - VMFS Filesystem

From this lesson, you learn about VMFS filesystem: from VMFS specifics, to on-disk layout, to VMFS data recovery approaches. In addition, we show how to recover data from a VMFS volume both automatically and in manual mode by assembling a VMFS volume from extents.