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LASERWRITER is a trademark of Apple Computer, Inc . • Published May 1989: ISSUE 1 ISBN 1 85250 068 9 \ Published by Acorn Computers Limited Part Number 0483,747 •• 11 Contents About this Guide Readership of this Guide· V Overview VI Conventions used in this Guide vu Introduction to System What is System Administration 1 Administration Guidelines to follow 2 Finding out about the Introduction 3 ' fllesystem Layout of the filesystem 3 Users of the filesystem 9 How the filesystem works 13 Mounting other UNIX filesystems 24 Starting up and Introduction 27 shutting down the Starting up the system . 27 .• .. ~ - .. system Shutting down the system •• 31 Adjusting your system 32 Using the RISCiXFS module 37 Security on the system 42 Maintaining the Introduction 45 filesystem Checking the filesystem using fsck 45 Tidying the filesystem 48 Filesystem maintenance scripts 51 Backing up the Introduction 61 filesystem Available commands 61 Using tar 62 Using cpio 63 Using dump and restore 67 Sample backup scripts 69 Contents Ill Adding and removing Introduction users Using useradmin Using groupadmin Using vipw Attaching peripheral Introduction Ul devices Available portS I Stages involved in connecting a device 111 Terminals ~) ~ Printers Im Modems lllJ SCSI peripherals I 0 I Using the floppy disc Introduction I I 7 utilities floppy disc.. device names 11 7 Formatting_. 9i~cs.. l I H Transferring information between machines I IIJ Using floppy discs as mountable UNIX filesystems 124 Setting up UUCP Introduction 127 Checking the serial line ll/'4 Setting up a UUCP name for your machine IN Setting up a UUCP login name 121) Setting up the UUCP files and directories 1211 Testing the UUCP link I ll Incoming UUCP I H Miscellany I ll Bibliography I I~ Reference Sections Reference Section A: The RISCiXFS module l l? Reference Section B: PostScript printer filter I '; I Reference Section C: Serial port connections 117 Reference Section D: Manual pages 161 Index • IV Contents About this Guide Readership of this 1 If you are using your RISC iX workstation as a stand-alone system, this Guide Guide provides you with enough information to start out as a Local System Administrator. If you are using your workstation on a network, contact your network System Administrator or alternatively refer to the Bibliography at the back of this Guide, which contains a list of books suitable for UNIX System Administration on a network. This Guide assumes that you have at least read the first few introductory chapters of the RISC iX User Guide and that you know how to log in to your system as root, as detailed in the Operations Guide. UNIX System Administration is a very large topic to broach in one Guide and there are many aspects that can only be fully appreciated by a thorough knowledge of the UNIX environment. ~-"~o not be put off by sometimes quite detailed information about the system . ,appearing in this Guide. Many example System Administration programs are available for you to use that will simplify the job of looking after your system . • If you wish to develop your System Administration skills further, you should refer to the Berkeley 4.3BSD System Manager's Manual which contains all the reference manual pages and supplementary documents for System Administrators as well as dipping into some of the books referenced in the Bibliography at the back of this G uide. About this Guide V Overview Here is a summary of the information that is contained in this G uide: Chapters Introduction to System Administration - gives an overview of the role of 11 System Administrator and explains why this role is so importanr in n UNIX environment. Finding out about the filesystem - a general description of the cont cnh nnd structure of the filesystem, with special emphasis on the parts of it rhat nn• ul interest to a System Administrator. Starting up and shutting down the system - describes the Jiffcrcnl procedures for booting the system up into RJSC iX and bringing the sysl cm down safely. This chapter also introduces the RJSC iX filing system modull' and sho~s how it can be u~ed for performing simple System Adminlsrr:a1lo11 tasks. Maintainitrg· •the filesystem - describes how to keep the fi lesystcm In n healthy state and also introduces some sample system maintenance scripts. Backing up the filesystem - details the various commands and utilities thnt yo u can use to backup your fil e~ystem. -., Adding and removing users - introduces the different methods available for adding and removing users from your system. Attaching peripheral devices - details the types of devices that can he attached to your system and discusses the stages involved in connecting them 10 your machine. Using the floppy disc utilities - describes all the fl oppy disc ut ili tiel\ t hnt are available o n your system. Setting up UUCP - describes how to set up UUCP on your system. Reference sections The reference sect ions at the back of the Guide contain supplcmt: nlilry information: The RISCiXFS module - gtves a full descriptio n of the * comm11"d" supported by the RISCiXFS module along with a list of I ikcl y c:rrilr messages that may be displayed. PostScript printer filter - a full listing of the PostScript printer fi lter thltt enables you to attach an Apple Laser Writer to your system vi About this Guldo Serial · port wnnections - wiring diagrams for attaching specific peripheral · devices to the serial port of your system. Manual pages · - contains the manual pages from section 8 of the 4.3BSD System Manager's Manual, that have been referenced in this Guide. An extensive bibliography is also included along with an index to help you find your way around the Guide . Conventions used In · The following typographical conventions are used throughout this Guide: this Guide Convention Meaning <DELETE> Press the key indicated. <CTRL-D> Hold down the first key and press the second. .J Press. the RETURN key . login: Text displayed on the screen. cat Text that you type in. filename A variable, where you should substitute what the word represents. For example: login: guest .J .• ~ ...... Another example: .. $ cat filename .J where filename is the name of the file; for example, 'readmel ': $ cat readmel .J £ .. About this Guide VII Introduction to System Administration What is System UNIX is a more complex system than single-user operating systems such as Administration? MS-OOS. This is because it was developed originally on machines intended for simultaneous multi-user access, with a team of operators assigned to attend to tapes and printers located well away from each user's terminal. One of the benefits .is that the system is multi-tasking, and many activities are simultaneously maintained by the UNIX kernel. Thus typical U NIX systems can be driving a printer, communicating with another system down a serial line and running a variety of tasks on a number of virtual terminals all at the same time. However, there are some drawbacks to this type of operating environment. For example: • You cannot just pull the plug to shut the machine down - it must be halted properly leaving everything in a tidy state. ... .. • Neither can you totally forget about what goes on behind the scenes and what housekeeping needs to be done from time to time to keep the system running smoothly. • You will also need to know about avoiding data loss and safeguarding your data by performing backups. • In future, you may also want to configure and adapt some of the aspects of the system to meet your own particular requirements, bypassing parts of the system you never use and avoiding questions to which you always give the same answer. In many cases you will find that UNIX is quite configurable, but you will need to find out a lot about the system before you start customising it.