Chapter 1. About Work Group Computing

The Advantages of Work Group Computing

Work group computing isn't just having a workstation on every desk. It means using the capabilities of your Silicon Graphics® systems and network to make something more than a collection of individual systems: a work group system. In a very real sense, work group computing means that all of your workstations, servers, printers, drives, and other devices make up a single system. A particular workstation might lack a CD-ROM drive, or start to run out of disk space during an intensive project. But if any other workstation has a CD-ROM, or if other workstations have ample disk space available, those resources are completely available because they're part of the work group system.

Work group computing offers power, resources, communication, flexibility, and capabilities that make each workstation much more than it could be as a standalone computer.

Added Capabilities

A work group system has capabilities that no set of individual computers can offer. Examples include centralized, automatic backup of important files, access to the hard disk storage on the entire work group system, and access to peripheral devices no matter where they are physically connected. When you use a work group system, you can use the whole system—not just the part of it that's on your desk.

Sharing Information

In work group computing, the information on one system can be available to other systems. If one member of your work group has a report, an image, or a document that someone else needs, it's easy to gain access to it.

An important component of sharing information in a work group computing system is consistent naming. All of the computers in the work group, for example, have names. Each computer must have a record of all of the other machine names, and of the names of the users of those machines. The Network Information System (NIS) provides an automated way of keeping records of those names, as well as a wealth of other information about all the machines and users in the work group.

How Work Group Computing Works

Work Group computing is a concept as well as a collection of hardware and software connected by a network. The concept is that the computing resources of an organization should be available at the time and place they're needed. When Jennifer needs additional disk space to store a massive 3D rendering, it doesn't make sense to purchase that storage when it already exists. It might exist somewhere else in the work group; on Ben's machine, for example. Work Group computing is primarily about designing a computing environment in which the resources of the whole system are flexible enough to meet the needs of any user, regardless of their physical location or their personal workstation's physical capabilities.

Clients and Servers

Clients and servers are integral to work group computing. Clients and servers are not physical machines; they are processes that have relationships to one another. A server is a process that provides some kind of service (for example, a database of the names of all of the machines on the network). A client is a process that makes use of a service (for example, by enabling a user to find a machine on the network). A server generally provides services to many clients. Both a client process and a server process can take place on the same machine, or on different machines. It doesn't matter which, and in fact, you often can't even tell!

Users and Administrators

Work Group computing also makes a distinction between users and administrators. This is a distinction in roles, not a distinction of people. As a member of your work group, most of the time your role is that of a user. You may be authoring content, using information, communicating, editing, or what-have-you. User roles involve activities in which the computing systems you use are tools—means to an end. Sometimes, however, you will take an administrative role. When you're backing up your files, setting up a password, or configuring a piece of software, you're an administrator, even if just for a few minutes. Administrator roles involve activities in which the computing systems are the objects of your attention.

Everyone in a work group is an administrator some of the time, and shares responsibility for some portion of the administration of the system. With power comes responsibility; that`s the responsibility that comes with the power of work group computing.

Work Group Computing Administration

Choosing an Administrator and Privileged Users

Within your own work group, it is important to decide which people will be responsible for keeping the system in good running order, and, if the system is connected to a network, who will work in conjunction with the network administrator to access network services. In some work groups, you may also need to designate a network administrator.

Administrative tasks are not, in many work group environments, allocated to just one person. Even if the work group tends to have one primary administrator, system administration is seldom that person's only job. Because administrative responsibilities are often shared in a work group, it is important that each user have some familiarity with those responsibilities.

About User Privileges and the Primary User

Because many people may use the same system, the system provides a built-in security scheme where you can grant different people different capabilities for changing the system. There are three levels of capability:


A user is any person who has a login account on a system. After logging in, users can change only their personal work areas. A user can run the graphical administration tools from the System toolchest, but the features of the tools that change system information are not available.

Privileged User

A person whose login account includes administrative privileges is a privileged user. When privileged users log in, they can change their personal work areas, and can use the graphical administration tools to change or customize the entire system (for example, to set up a disk or create a login account). There can be more than one privileged user on the same system.


The administrator of a system is the person who can use the most privileged account, the root account. This person should have a personal login account for daily use, but, when there are serious system problems to correct, the person logs in to the root account to change system information using the graphical tools or using the IRIX™ shell.

The administrator has all the capabilities of a privileged user, as well as the ability to change information in the root account (such as the password) and to log in to an IRIX shell as root. Because there is only one root account on a system, there is only one administrator per system. The System Manager window for a particular system includes the name of the system's administrator so other users know who to contact for help.

In a work group computing environment where each person has one system, the responsibilities of users, privileged users, and administrators are often allocated in this manner:

  • Each person, as the “system owner,” is completely responsible for maintaining his or her own system. That person is both a privileged user and the administrator for that system. Usually the person performs administrative tasks while logged in to a personal account. But when the IRIX shell with administrative privileges is needed, the person logs out and logs back in to the root account.

  • The system owner logs in as a privileged user in order to add login accounts for other people who occasionally need to use the system. If one of these users ever needs to perform administrative tasks, the system owner adds privileges to the account to make that user a privileged user.

For environments in which one person uses a particular system much more frequently than anyone else (where the person is essentially the system's owner), you can designate that person as the primary user. The primary user does not necessarily have any special access privileges, but the person's name appears along with the administrator's name in the system's System Manager window so other users know who uses the system regularly. There is only one primary user per system.

Note: The System Setup tool supports the model where one person has one system that he or she must maintain. When you create a login account for a person using this tool, it designates that person as the primary user, and also makes the person a privileged user. If necessary, you can later use the User Manager to remove administrative privileges or assign the title of primary user to someone else.

The Responsibilities of Privileged Users

A privileged user can use administration tools to perform the tasks listed below. For more information about these tasks, see the Personal System Administration Guide.

  • Setting up the system initially as a standalone system or as a member of an existing network.

  • Creating login accounts so all users of the system can access it. If the system will be connected to a network, the administrator may work in conjunction with the network administrator.

  • Connecting any peripheral devices and configuring software so that the devices work properly.

  • Monitoring and troubleshooting the system to keep it working efficiently and properly.

  • Contacting the network administrator before connecting a system to the network. The network administrator provides information that uniquely identifies each system on the network and ensures that the regular users of a system can have accounts on other systems on the network.

  • Making all, some, or none of a system's directories available to all, some, or none of the other systems and users on the network.

  • Providing access to printers on other systems so the users of a system can send files to them.

  • Providing access to disk space that's available on other systems on the network.

The Network Administrator's Role

The responsibilities of a network administrator vary greatly from site to site. In a work group environment, the network administrator is often responsible for these tasks:

  • Setting up and maintaining the network so connections are reliable and data is transferred as quickly as possible.

  • Creating, maintaining, and periodically distributing a list of all systems and users so that each has a unique identity on the network.

  • Setting up and maintaining network services such as electronic mail and the Network Information Services (NIS).

Using System Administration Tools

As the administrator or privileged user you can use two different types of tools:

  • The System toolchest provides a collection of graphical system administration tools.

  • The IRIX shell accepts IRIX commands that you use for more advanced administrative tasks.

This online information describes how to use the graphical tools in the System toolchest to perform as many administration tasks as possible; in cases where no graphical tools support a task, you must use IRIX commands or edit system files. If you prefer to perform all administrative tasks without using the System toolchest, see the IRIX Admin manual set (choose “Online Books” from the System toolchest, and look in the SGI_Admin bookshelf). Regardless of whether you edit system files manually or let the graphical tools do it for you, you are changing the same system files.

The System Toolchest

The administrative tools that you'll use most frequently are in the System toolchest menu; you run a tool by choosing it from the menu. The first tool in the menu is the System Manager. Tools that you use less frequently appear when you choose “System Admin Tools” from the Tools menu in the System Manager window.

The System toolchest includes these tools:

  • System Manager

  • Disk Manager

  • User Manager

  • NFS Mount Manager

  • Printer Manager

  • Software Manager

  • Backup & Restore

  • View System Log

  • Run Confidence Tests

Each tool is described in a section below.

System Manager

Using the System Manager, a user can perform these tasks::

  • Determine which of the system's resources are available for use by other systems on the network.

  • Check the hardware and software inventory of the system.

  • Get business card information about the system's primary user and administrator.

In addition, a privileged user can perform these tasks:

  • Run all the system administration tools

  • Designate the primary user.

Disk Manager

The Disk Manager shows how much disk space you are using and how much is still available. Privileged users can specify when the system should warn that the disk is nearly full. When you install a new disk, a privileged user also uses this tool to specify a directory from which to access the disk (the directory from which you access a disk is called the mount point for that disk).

User Manager

The User Manager enables users to perform these tasks:

  • View information about their own login account.

  • View information about other login accounts.

  • Change business card information about their own account.

In addition, privileged users can use the User Manager to create, change, and delete user login accounts.

NFS Mount Manager

The NFS® Mount Manager is available only on systems that have the optional NFS software installed. The NFS Mount Manager lets privileged users access (mount) directories on other systems so that users can access the directories as if they resided on the local system.

Printer Manager

With the Printer Manager, users can view the list of available printers and drag printer icons onto their desktops for use. Additionally, privileged users can use the Printer Manager to set up the software for local or remote printers so the system can access the printers.

Software Manager

Users and privileged users can view a list of installed software by using the Software Manager. The Software Manager also enables the administrator to install and remove software.

Backup & Restore

Backup & Restore enables users to to back up their own files and directories. The administrator can use Backup & Restore to create full system backups from which the entire system can be restored in the event of a serious system failure.

View System Log

View System Log displays a log of all the system messages, and lets a privileged user customize when and how users should be notified of system problems.

Run Confidence Tests

Run Confidence Tests displays a window in which users can test various peripherals and system components, such as the mouse, keyboard, and monitor.

Logging In as root Through a Shell Window

Only the administrator can perform administrative tasks that are not supported by the graphical tools since these tasks require the use of the root account in a shell window. The home directory for the root account is the root (/) directory of the filesystem. The user logged in to the root account can move, change, and delete every file and directory on the system, regardless of who owns them and what type of permissions they have set. Be sure to create a password for this account that only the administrator knows.

Note: Some UNIX® and IRIX documents refer to the user of the root account as the superuser rather than the administrator.

When you're already logged in as a regular user, you can start a shell window and log in as root by following these steps:

  1. Choose “Unix Shell” from the Desktop toolchest.

  2. Position your cursor within the new window and enter:

    % login root

    If a prompt for a password appears, type the password, then press Enter. If a prompt appears but the root account has no password, just press Enter. (See “Customizing System Account Information” to create, change, or remove a password.)

    You are now logged in to the root account and are located in the root (/) directory. When you are logged in as root, the IRIX prompt is a pound sign (#) rather than a percent sign (%).

    To log out of the root account, enter:

    # logout

    The shell window disappears.