TABLE OF CONTENTS Imagination is more important than knowledge.
Albert Einstein
In this chapter, we cover the UNIX file system (UFS), [1] which is the first of two general-purpose, local file system types (the second being AdvFS) that are fully supported in all versions of Tru64 UNIX.
We begin this chapter by discussing the history of UFS. Then, we cover some of the file system's on-disk structure details as well as some of the inmemory structures. Next, we discuss some of the tools available for creating, tuning, and examining UFSs. Also, we cover the tools for troubleshooting and repairing corrupted file systems. We include brief coverage of backups and quotas, concluding with information about the memory-based UFS.
[1]The acronym UFS has been used in other texts to stand for the unified file system, which is another term that refers to the UNIX file system, based on the Berkeley fast file system. Here, when we refer to UFS we are using it as a shorthand for the UNIX file system.
The UFS has been around in various forms since version 7 of UNIX. We endeavor here to provide readers with some historical perspective in order to enhance their understanding of how the system has evolved over time and some of the design decisions that were made. This information provides a basis for describing how the file system behaves today.
This section first discusses the original file system for UNIX and the newer file system based...
