Overview of DIGITAL UNIX System Administration

1 Overview of DIGITAL UNIX System Administration

This chapter surveys many of the tasks that are performed by Digital UNIX system administrators and points to the places in this manual and in other sources that describe these tasks.

1.1 The Digital UNIX System Administrator

As administrator of a Digital UNIX operating system, you work in the following envrionment:

The hardware and software

The hardware environment is a client Alpha workstation in a local area network being served by an Alpha server. The client and server machines are running supported versions of the Digital UNIX operating system software.

The administrative tasks

As administrator, you perform operational tasks to set up, monitor, maintain, and exploit available software and hardware resources.

The user interface to the operating system
For many system administration tasks, you can choose to use the UNIX command line interface or the SysMan graphical user interface.
This manual describes the UNIX command line interface for the tasks.
The SysMan interface is now recommended by Digital for interacting with the operating system. If possible, you should examine whether or not you can use this interface for your administrative tasks. See Section 2.2 for more information.

This manual does not include information about planning an operating system environment. For information about planning operating system environments, see your local Digital representative.

Information about administering network-related tasks is documented in the Digital UNIX Network Administration manual.

The information you need to install the Digital UNIX operating system is contained in the Digital UNIX Installation guide, and all the information you need to update the Digital UNIX operating system is contained in the Digital UNIX Update Installation card.

The following sections survey the contents of the chapters in this manual. In general, the first few chapters contain information about the setup tasks you perform the first few hours after installing or updating new operating system software.

The several remaining chapters contain information about the schedule- and event-driven tasks that make up the bulk of a system administrator's work. These tasks use the operating system components, its services, or features to maintain the performance of the operating system and the satisfaction of its users.

1.2 Starting Up and Shutting Down the System

Chapter 3 contains instructions for booting and for shutting down systems. You will need this information for the following tasks:

System testing or troubleshooting
When you test or troubleshoot your system, you need to move between run levels, for example, from multiuser mode to single-user mode.
Setting the system clock
If your system has been powered down for an extended amount of time, you will need to set the system clock.

1.3 Customizing the System Environment

Periodically, you will need to tailor your system to fit your needs. For example, you might need to:

Modify system files to add information about new devices or to invoke certain programs when the system moves from one run level to another.
Specify commands to be run automatically at a specific time.
Set your system to a different locale. The Digital UNIX operating system includes National Language Support (NLS) for multiple environments.

Chapter 4 describes how to customize your system for these purposes, and also discusses how to customize:

Internationalization features for programmers and users
Your time zone
The environment needed to establish a system that meets the requirements of your site's security policy

The tools you use to maintain adequate performance for operating system components and for user applications

The power consumption of certain hardware subsystems

1.4 Configuring the Kernel

You may need to tune your system to enhance performance, add new devices, or install new software. These changes may require you to modify your system configuration file. If you modify the system configuration file, thereby reconfiguring the kernel, you must compile and boot a new system image for the changes to take effect. Chapter 5 includes the following information:

Descriptions of the configuration files and the tunable options in the files
Instructions for configuring, compiling, and booting a new kernel
Instructions for configuring a STREAMS module or driver into your system
Instructions for administering loadable drivers

1.5 Administering Dynamic Device Recognition

Chapter 6 describes the components you use and the tasks you perform in order to administer the Dynamic Device Recognition capabilities of your operating system. Dynamic Device Recognition (DDR) is a framework for describing the operating parameters and characteristics of SCSI devices to the SCSI CAM I/O subsystem.

You use the ddr_config(8) utility and the ddr.dbase(4) text database to make changes to the subsystem whenever you change the devices in the SCSI CAM I/O subsystem. You make these changes after the operating system is installed and without needing to reboot the operating system.

The administrative tasks are:

Compiling the DDR database
Converting the cam_data.c file to entries in the DDR database

You use the ddr_config utility to accomplish both tasks.

In addition, this chapter contains instructions for maintaining other terminals and mass storage devices on your system. The tasks involved include the following:

Making a new kernel (for disk and tape devices only)

Modifying the proper system files

Making devices known to your system

1.6 Administering the UNIX File System

Chapter 7 contains information to help you perform the following file system and disk management tasks:

Allocate more swap space or change your method of swap space allocation
Create, check, tune, maintain, and mount file systems
Determine how your disk space is being utilized
Repartition the file systems on a disk

1.7 Administering the Advanced File System

Chapter 8 describes the Advanced File System (AdvFS) component. AdvFS offers rapid crash recovery, high performance, and a flexible structure that enables you to manage your file system while it is on line.

1.8 Administering the Logical Storage Manager

The Logical Storage Manager (LSM) software has disk management capabilities that increase data availability and improve disk I/O performance. System administrators use LSM to perform disk management functions dynamically without disrupting users or applications accessing data on those disks. Chapter 9 describes the elements of LSM that are most commonly used by a system administrator.

1.9 Administering User Accounts and Groups

Use the information in Chapter 10 to perform the following tasks:

Add, modify, and remove user accounts
Add and remove groups

1.10 Administering the Print Services

Use the information in Chapter 11 to perform the following printer management tasks:

Add and remove printers and change the configuration of an existing printer
Show the status of a printer and control the printer; for example, delete print requests and enable and disable printers
Enable printer accounting

1.11 Administering the Archiving Services

Use the information in Chapter 12 to perform the following tasks:

Choose which file systems to back up so that all the files on your system, data files as well as system files, are protected from loss
Choose a backup schedule so that you do not have to back up all the files in a file system at each backup
Set up a schedule for performing a full backup of each file system on your entire system, including all the system software
Set up a routine backup schedule to make it easier to remember which backup to do each day
Use the rdump command to make backups on a remotely located tape device
Automate the backup process by using shell scripts
Restore a file system by using the restore or the vrestore command
Restore files from a remote tape device by using the rrestore command
Restore the root and /usr file systems

1.12 Administering System Accounting Services

Chapter 13 describes how to set up and use accounting to track system resources. It describes how to perform the following accounting administration tasks:

Set up the resource accounting software
Enable automatic accounting
Create accounting reports
Make sure that the accounting files are a manageable size

1.13 Administering Events and Errors

Chapter 14 contains information on system events and errors. First, it describes how you can use the system exercisers to discover potential system problems. With this information you can act to prevent events or errors from occurring. Next, the chapter discusses system events and the components you employ to react to these events. Use the information in this chapter to perform the following tasks:

Change the default event-logging configuration
Examine the event-logging files to ensure that problems do not exist
Make sure that the event-logging files are a manageable size

1.14 Appendixes

The appendixes to this manual describe auxiliary information, seldom-used utilities, and components which are scheduled for retirement, but that are documented for backward compatibility.

1.14.1 Device Mnemonics

Appendix A identifies and defines the mnemonics that you use to attach any hardware or software device to your system. You specify the mnemonics when you create the character or block special files that represent each of the devices.

1.14.2 SCSI/CAM Utility Program

Appendix B describes the SCSI/CAM Utility Program (SCU), which interfaces with the Common Access Method (CAM) I/O subsystem and the peripheral devices attached to Small Computer System Inferface (SCSI) busses. This utility implements the SCSI commands necessary for manual maintenance and diagnosis of SCSI peripheral devices and the CAM I/O subsystem.

1.14.3 CI and HSC Hardware

Appendix C describes the CI bus and Hierarchical Storage Controller (HSC) hardware. This appendix contains information about hardware and software installation, setup, and restrictions. It also describes how to boot an HSC controller and disk and how to share HSCs among hosts.

1.14.4 Using the uerf Error Logger

The uerf error logging utility has been scheduled for retirement. Its use is described here for backward compatibility purposes.

1.14.5 Administering Specific Hardware Devices

Appendix E Explains how to install specific hardware devices available on some processors.