ULTRIX-32 Supplementary Documents System Manager

This document is "ULTRIX-32™ Supplementary Documents, Volume 3 System Manager," published by Digital Equipment Corporation (Copyright 1984, 1988). It serves as a collection of articles from computer scientists and program developers at Bell Laboratories and the University of California at Berkeley, aimed at system managers responsible for the installation, administration, and daily maintenance of the ULTRIX-32 Operating System, Version 3.0, which is based on 4.2BSD UNIX.

The document is organized into five main parts:

1. Operating System Changes: Details improvements from 4.1BSD to 4.2BSD, focusing on a redesigned Fast File System for VAX hardware (offering block size optimization, file locking, symbolic links, and atomic rename operations), new interprocess communication facilities (sockets, signals), enhanced disk quotas, and the introduction of the dbx symbolic debugger and the sendmail internetwork mail router.
2. Maintenance and Administration: Provides practical guidance for system managers on crucial utilities. This includes managing disk quotas (setting and enforcing limits, user perspectives, administration), using fsck for file system consistency checks and repairs (interactive and non-interactive modes, error conditions), and the installation and operation of the sendmail utility (configuration, mail queue processing, debugging, and tuning).
3. Communications: Explains the underlying communication software. It covers a "Primer" on 4.2BSD Interprocess Communication (socket types, creation, binding, connection, data transfer, I/O multiplexing) and "Networking Implementation Notes" (internal structure, memory management, routing, raw sockets). It also includes a background paper on sendmail's design as an internetwork mail router and discusses other standard networking utilities like ftp and telnet.
4. Security Considerations: Addresses security aspects of the UNIX system, particularly focusing on protecting against crashes and unauthorized access. It delves into password security (a case history of its development, including slower encryption, less predictable and salted passwords, and the threat of DES chips), file protection bits, UID/GID functions, and precautions for superuser accounts, set-UID programs, and the mount command.
5. Supporting Documents: Offers historical context and practical information for system setup and customization. This part details specific changes to the Kernel in 4.2BSD from previous versions, comprehensive procedures for installing and operating 4.2BSD on the VAX (bootstrapping, disk formatting, kernel configuration with config, and setting up network and mail systems), and information on the UUCP (Unix-to-Unix Copy) dial-up network for file transfers and remote command execution.

The document emphasizes that while some specific information may be dated, the core concepts and methodologies remain relevant for understanding and managing ULTRIX-32 systems.