Distributed File System

1. Distributed File System

2. Definition • Stands for "Distributed File System." A DFS manages files and folders across multiple computers. It serves the same purpose as a traditional file system, but is designed to provide file storage and controlled access to files over local and wide area networks. • Even when files are stored on multiple computers, DFS can organize and display the files as if they are stored on one computer. This provides a simplified interface for clients who are given access to the files.

3. Why Was DFS Created? • Having files spread across multiple file servers confuses users and makes it difficult for them to find their files. • Sharing files in a single location creates performance lag when they are accessed across slow WAN links, and a single point of failure when those links go down. • It is difficult to backup critical files and data when they are dispersed haphazardly on multiple file servers at multiple remote locations.

4. To Solve the Problems • DFS Name Spaces • DFS Replication

5. DFS Namespace • A DFS namespace is a virtual directory tree that points to or references one or more network shares called targets.

6. DFS Architecture

7. DFS Modes • Stand-alone • Domain-based

8. Stand-alone DFS • Accessed via: \\Servername\DFSRoot • Can be: DC, Member server or stand-alone • Namespaces: Supports only one • Stored in: Registry and system cache • Active Directory: Not required

9. Domain-Based • Accessed via: \\Domain-name\DFSRoot • Can be: DC, Member server • Namespaces: Supports MULTIPLE • Stored in: Active Directory • Active Directory: Required

10. DFS Replication • DFS replication is a multi-master replication service that maintains copies of shared files and folder on multiple servers throughout the organization. • The replication service is responsible for synchronizing files across replicas.