2    System Management

This chapter introduces some of the system management features of the Tru64 UNIX operating system. The following topics are discussed:

2.1    Installation

Tru64 UNIX supports Full and Update Installations either from a CD-ROM or across the network from a Remote Installation Services (RIS) server. It also supports system cloning.

2.1.1    Full Installation

A Full Installation lets you install Tru64 UNIX on new and existing systems. You can use the recommended settings for the file system layout, kernel components, and software or you can make your own customized selections.

You can use either a graphical interface or a text-based interface to install the operating system quickly and easily. The graphical interface (available only on graphics-capable systems) steps you through each phase of the setup process and lets you go backward and forward at any time during the installation. The text-based interface also guides you through each setup phase and you can go back and change your answers, if necessary.

Figure 2-1 shows the initial window of the graphical interface for a Full Installation.

A Full Installation creates new file systems and swap space and overwrites existing system and user-created files on the disk partitions where the file systems and swap spaces are to be installed. You have the option to use default values for the disk layout and swap space allocation or to completely customize the locations of file systems and swap space.

Figure 2-1:  Initial Window of Full Installation

Major changes to the Full Installation process since the 5.0 release include the following:

You can customize and extend the Full Installation by creating custom scripts or programs to run at three process points during installation: before the installation begins, after software subsets load, and after the system reboots. The files you create can be loaded on a diskette, a CD-ROM, or a RIS server for use by the installation process.

A Full Installation creates a Configuration Description File (CDF) called install.cdf that can be used to replicate the Full Installation on similar systems (see Section 2.1.3). You can also capture configuration data into a config.cdf file from a running system and replicate the following during a Full Installation:

For more information on Full Installations, see the Installation Guide and the Full Installation Quick Start card.

2.1.2    Update Installation

An Update Installation updates Tru64 UNIX from an earlier version of the operating system. You can use the Update Installation process to update your system from Versions 4.0F and 5.0 to Version 5.0A. An Update Installation preserves the following:

You should not perform an Update Installation if you want to change the type, location, or size of file systems or if you want to install optional software.

The software subsets that comprise the operating system are known as base software subsets. During an Update Installation, the base software subsets that are already installed are updated to the new version. In addition, any mandatory base software subsets that are introduced in the new version are installed automatically. Base software subset names start with the prefix OSF.

Worldwide Language Support (WLS) software subsets that are already installed are updated to the new version. In addition, any mandatory WLS software subsets that are introduced in the new version are installed automatically. WLS software subset names start with the prefix IOS.

When invoked with the -u option, the Update Installation process runs in unattended mode, which means that barring any problems with the update, no user interaction required. The only exception to this is the switching of CD-ROMs if WLS software is being updated. The -u option builds a kernel with all kernel components and does not provide the chance to archive obsolete files.

Beginning with the Version 5.0 release, an analysis phase was added to the beginning of the Update Installation process to analyze your system for the following:

If layered product or nonfatal file type conflicts are discovered, you can resolve them directly from the Update Installation user interface; there is no need to exit the installation, resolve the conflict, and restart the installation. If your system does not have enough available disk space for new software and room for Update Installation processing, disk space recovery options are available directly from the Update Installation as well.

Figure 2-2 shows the first window of the Update Installation procedure.

Figure 2-2:  Initial Window of Update Installation

You cannot install additional optional software subsets during an Update Installation nor update layered products. You can, however, install additional optional software subsets by using the setld utility when the Update Installation is complete (see Section 2.1.4). To update layered products, it may be necessary to delete the existing version of the product and install the new version that is designed to operate with the new operating system version. The Update Installation notifies you accordingly.

The Update Installation features are classified into two types:

Table 2-1:  User-Controlled Features of the Update Process

User Options Description
Unattended Update Installation If you do not need to select optional kernel components or archive obsolete files, you can invoke the Update Installation with the -u flag to run the update without any user intervention.
Kernel Component Options You have the option to build either mandatory only or all kernel components into the kernel, or you have the option to interactively select optional kernel components.
Archive Obsolete Files You have the option to archive obsolete files before they are automatically removed by the Update Installation.

Table 2-2:  Built-In Features of the Update Process

Built-In Feature Description
Notification of conflicting layered products Notifies you when an installed layered product may not be compatible with the new version of the operating system; this layered product may need to be reinstalled later.
Remove layered products that prevent the update from continuing Upon your confirmation, removes layered products that prevent the update from continuing.
Update base operating system and WLS software to new version Updates existing installed subsets and installs new mandatory subsets introduced in the new version.
Check for changed file types Checks for file types that have been changed. The update might not be able to proceed if certain conflicts are found.
Disk space recovery Provides the option to remove unnecessary software subsets and .PreUPD, core, and extra kernel files to recover disk space if there is not enough file space to complete the update.
Execute instructions provided in user-supplied files You can customize an Update Installation by creating and moving user-supplied scripts, programs, or executable files to the appropriate location. If the update process finds files with the correct names in the appropriate locations, the files are executed.

For more information on the Update Installation, see the Installation Guide and the Update Installation Quick Reference Card.

2.1.3    Cloned Installations

Installation Cloning lets you duplicate the installation characteristics (that is, the file systems and installed software) from a running system onto one or more systems with the same or similar hardware configuration.

The use of Installation Cloning to mass-install systems has the following benefits:

When you install the current version of the operating system on a machine, the installation process automatically generates a configuration description file (CDF) that contains a record of the installation setup data you specified, and therefore contains all of the installation information required to perform the same installation on a target system.

Installation cloning is not supported between different releases of the operating system because CDFs created by other versions of the operating system are not compatible with the current version. Therefore, if you want to clone Version 5.0A onto a target system, you must create the CDF by performing a Version 5.0A Full Installation.

Systems that are installed by the cloning process must have the same disk configuration as the system where the CDF was generated. This means that the disks used for the / ( root ), /usr,/var, /usr/i18n file systems and swap areas on both systems must have the same disk type and the same device name. It is possible, however, to accommodate slight differences in configuration.

For information about Installation Cloning, see the Installation Guide -- Advanced Topics.

2.1.4    The setld Utility

The setld utility allows system administrators to install software subsets, list installed subsets, and delete subsets that are formatted according to the guidelines set forth in Guide to Preparing Product Kits. For example, a system administrator might use the setld utility to install optional subsets that were not installed during a Full or Update Installation of the operating system.

Application programmers should use the Compaq kitting process when packaging software subsets designed to be installed on Tru64 UNIX systems.

For more information on the setld utility, see the Installation Guide and the setld(8) reference page.

2.2    Configuration

If your system has graphics capabilities, you can use SysMan System Setup (Figure 2-3) to set up your system after the Tru64 UNIX software is installed. System Setup enables you to invoke the Quick Setup and Custom Setup applications.

The first time you log in as superuser or root after a system installation or the first time you log in to a factory-installed software (FIS) system, you will have the option to use either Quick Setup to configure a limited set of system parameters (including network and printer parameters) or use Custom Setup to set up your system for general use.

Figure 2-3:  System Setup

Quick Setup has a wizard-like design that lets you enter a minimal amount of key information. Quick Setup updates your system with the basic configuration needed to get a client system up and running, including network connection, mail, and print capabilities. Quick Setup should satisfy the configuration needs for most systems. Even for systems that will be configured as servers, it is recommended that you use Quick Setup first to configure your system then customize it with advanced applications in Custom Setup. Figure 2-4 illustrates Quick Setup.

Figure 2-4:  Quick Setup

Custom Setup lets you perform sophisticated system configuration that is beyond Quick Setup's scope. When Custom Setup runs, it examines your system and presents a list of configuration applications that are relevant for your system; these applications are displayed as a checklist. Once you have accessed an application, a checkmark appears next to the application. For information about individual applications, see the Welcome to SysMan online help. Figure 2-5 illustrates Custom Setup.

Figure 2-5:  Custom Setup

When you are logged in as superuser or root, you can invoke the SysMan System Setup at any time by clicking on the Configuration Checklist icon in the System_Administration folder, or by entering the following command on the command line: 


# /usr/sbin/checklist

The utilities you see listed with the Custom System checklist depend upon which subsets are installed on your system. For example, if the optional security subset were not installed, the Audit Configuration application would not be displayed. The following list represents some of the applications you might see with the Custom System checklist:

Many of the SysMan System Setup applications are also available in ASCII format for use on character-cell displays.

For more information about system setup in general, see the Installation Guide, the System Administration guide, the Network Administration guide, the Software License Management guide, and the setup(8) reference page.

2.3    Logical Storage Manager

The Logical Storage Manager (LSM) software is a layered Tru64 UNIX application that allows you to manage disks and partitions as a flexible pool of storage from which you create LSM volumes. You configure file systems, databases, and applications to use an LSM volume instead of a disk partition. The benefits of using an LSM volume instead of a partition include the following:

LSM is an optional subset located on the Tru64 UNIX CD-ROM. You can install LSM when you install the Tru64 UNIX operating system software or at a later time.

Without an LSM license, you can use LSM to join together disks and partitions, then create an LSM volume to use that storage. All other LSM features require an LSM license. Contact your local Compaq office or your Compaq authorized reseller for information about Compaq's licensing terms and policies or purchasing an LSM license.

The LSM graphical interface lsmsa uses the Java run-time environment to provide a method of invoking LSM commands and to monitor LSM file status. When the main window is displayed, a hierarchical view of LSM objects is presented. Clicking on an object displays the objects of that type and a table of information about them.

2.4    System Management Utilities

The SysMan application suite, introduced in Version 5.0, makes your job as a system or network administrator easier by providing you with an application for each of your administration tasks, such as installation, configuration, daily administration, monitoring, kernel and process tuning, and storage management. You can access these applications through the SysMan pop-up menu from the CDE front panel when you log in as root. Most of the applcations also have supported command-line counterparts.

Although the SysMan utilities were designed to take advantage of the Common Desktop Environment (CDE), most will work outside of CDE with other window or display managers. For example, the following command invokes the Network Interface Configuration tool: 


# sysman interface

Many of the SysMan utilities are also available as text-based interfaces for use on character-cell displays.

2.4.1    The SysMan Menu

The SysMan Menu (Figure 2-6) provides a menu of system management tasks in a tree-like hierarchy with branches of general categories, and leaves for actual tasks. The categories are Accounts, Mail, Monitoring and Tuning, Networking, Printing, Security, Hardware, Software, Storage, Support and Services, and General Tasks. You can expand or contract a branch to show the subbranches and leaves within a main branch. Selecting a leaf invokes a task that opens a dialog box for performing the task.

The SysMan Menu is invoked from the CDE front panel when you are logged in as root, or directly from the command line by entering the /usr/sbin/sysman command. Because the SysMan Menu can be run in CDE, HTML, or ASCII text environments, you can use the SysMan Menu on an X11 capable display, on a personal computer running Microsoft Windows products, Linux, or the Macintosh Operating System, or on a character cell terminal.

Figure 2-6:  The SysMan Menu

The SysMan Menu offers the following typical applications, depending on what options are installed and configured on the local system: 

- Accounts [accounts]
    | Manage local users [users]
    | Manage local groups [groups]
    | Manage NIS users [nis_users]
    | Manage NIS groups [nis_groups]
- Hardware [hardware]
    | View hardware hierarchy [hw_hierarchy]
    | View cluster [hw_cluhierarchy]
    | View device information [hw_devices]
    | View central processing unit (CPU) information [hw_cpus]
- Mail [mail]
    | Configure Mail [mailsetup]
    | Manage users' mail accounts [mailusradm]
- Monitoring and Tuning [monitoring]
    | View events [event_viewer]
    | Set Up Insight Manager [imconfig]
    - Class Scheduling [class_sched]
        | Configure Class Scheduler [class_setup]
        | [Re]Start Class Scheduler [class_start]
        | Stop Class Scheduler [class_stop]
    | View Virtual Memory (VM) statistics [vmstat]
    | View Input/Output (I/O) statistics [iostat]
    | View Uptime statistics [uptime]
- Networking [network]
    | Network Setup Wizard [net_wizard]
    - Basic Network Services [networkbasic]
        | Set up Network Interface Card(s) [interface]
        | Set up static routes (/etc/routes) [route]
        | Set up routing services (gated, routed, IP Router) [routing]
        | Set up hosts file (/etc/hosts) [host]
        | Set up hosts equivalency file (/etc/hosts.equiv) [hosteq]
        | Set up remote who services (rwhod) [rwhod]
        | Set up the networks file (/etc/networks) [networks]
        | Set up Asynchronous Transfer Mode (ATM) [atm]
    - Additional Network Services [networkadditional]
        - Domain Name Service (DNS(BIND)) [dns]
            | Configure system as a DNS server [dns_server]
            | Configure system as a DNS client [dns_client]
            | Deconfigure DNS on this system [dns_deconfigure]
        - Serial Line Networking [serial_line]
            - Point-to-Point Protocol (PPP) [ppp]
                | Create option files [ppp_options]
                | Modify pap-secrets file [pap]
                | Modify chap-secrets file [chap]
            | Configure system for UNIX-to-UNIX copy (uucp) connections
[uucp]
        - Network Time Protocol (NTP) [ntp]
            | Configure system as an NTP client [ntp_config]
            | View status of NTP daemon [ntp_status]
            | {Re}start NTP daemon [ntp_start]
            | Stop NTP daemon [ntp_stop]
        - Network File System (NFS) [nfs]
            | View NFS configuration status [nfs_config_status]
            | Configure system as an NFS client [nfs_client]
            | Deconfigure system as an NFS client [nfs_deconfig_client]
            | Configure system as an NFS server [nfs_server]
            | Deconfigure system as an NFS server [nfs_deconfig_server]
            | View NFS daemon status [nfs_daemon_status]
            | {Re}start NFS daemons [nfs_start]
            | Stop NFS daemons [nfs_stop]
        | Configure Network Information Service (NIS) [nis]
        | Configure Local Area Transport (LAT) [lat]
        | Set up the system as a DHCP Server (joind) [joind]
    | View network daemon status [dmnstatus]
    | {Re}start network services [inet_start]
    | Stop network services [inet_stop]
- Printing [printers]
    | Configure line printers [lprsetup]
- Security [security]
    | Configure Division of Privileges (DOP) [dopconfig]
    | Security Configuration [secconfig]
    | Audit Configuration [auditconfig]
- Software [software]
    - Installation [install]
        | Install software [setldload]
        | List installed software [setldlist]
        | Remove installed software [setldd]
        | Cleanup after an OS update (updadmin) [updadmin]
    | Register license data [lmfsetup]
- Storage [storage]
    - File Systems Management Utilities [filesystems]
        - General File System Utilities [generalfs]
            | Dismount a File System [dismount]
            | Display Currently Mounted File Systems [df]
            | Mount File Systems [mount]
            | Share Local Directory (/etc/exports) [export]
            | Mount Network Directory (/etc/fstab) [net_mount]
        - Advanced File System (AdvFS) Utilities [advfs]
            | Manage an AdvFS Domain [domain_manager]
            | Manage an AdvFS File [file_manager]
            | Defragment an AdvFS Domain [defrag]
            | Create a New AdvFS Domain [mkfdmn]
            | Create a New AdvFS Fileset [mkfset]
            | Recover Files from an AdvFS Domain [salvage]
            | Repair an AdvFS Domain [verify]
        - UNIX File System (UFS) Utilities [ufs]
            | Create a New UFS File System [newfs]
    - Logical Storage Manager (LSM) Administration [lsm]
        | Initialize the Logical Storage Manager (LSM) [volsetup]
        | Logical Storage Manager (LSM) Administrator [lsmmgr]
    | Create a Bootable Tape [boot_tape]
- Support and Services [support]
    | Create escalation report [escalation]
    | Create configuration report [config_report]
- General Tasks [general_tasks]
    | Shutdown the system [shutdown]
    | Quick Setup [quicksetup]
    | Configure Prestoserve software [presto]
    | Configure X Display Manager [xsetup]
    | Cloning setup information [cloneinfo]
    | Command line interface information [sysmancli]

A keyboard accelerator is provided for each menu item, such as [ufs]. The accelerator enables you to quickly launch a specific tool directly from the command line; for example:

# sysman ufs

2.4.2    The SysMan Station

The SysMan Station (Figure 2-7) provides a high profile view and status of a system's physical and logical objects. It is intended to be the central point from which to manage a Tru64 UNIX system. The SysMan Station launches other SysMan utilities to perform the tasks. You can launch the SysMan or invoke applications directly from the Tools menu in the SysMan Station. It can run on a standard Java capable display (such as a UNIX workstation) or within a PC's browser, or it can be downloaded and run directly on a PC.

You can use SysMan Station to perform the following tasks:

You can launch the SysMan Station directly from an icon on the CDE front panel when you log in as root, or you can enter /usr/sbin/sms from the command line.

Figure 2-7:  The SysMan Station

2.4.3    The CDE Application Manager

If you are running Tru64 UNIX with the CDE desktop, you have access to the CDE Application Manager. The System_Admin group on the CDE Application Manager launches the following SysMan utilities:

The icons in the CDE Application Manager, System_Admin folders usually invoke a SysMan menu utility. For example, if you click on the DNS (BIND) icon in the Configuration folder the SysMan Menu is invoked, showing only the SysMan Menu DNS options. However, in a few instances, clicking on an icon will launch an X11-compliant graphical user interface (GUI).

These X11-compliant applications are distinctly different from the analogous tools available from the SysMan Menu. The GUIs take advantage of features that are only available in the X windows user environment, such as the ability to perform operations by dragging and dropping icon representations of objects. For example, when you click on the Account Manager icon in the CDE Daily_Admin folder, it does not invoke the SysMan Menu; instead, it displays the X11-complaint dxaccounts GUI.

This means that there might be two or more interfaces that you can use to perform an identical task, depending on your personal preference for a particular user environment.

The System_Admin group also contains the following categories of system administration groups:

2.5    Performance and Event Management

Tru64 UNIX provides various utilities that you can use to monitor and manage your system and its events. The following sections provide a brief overview of these utilities; for more information and instructions on using them, see the System Administration guide and the Installation Guide.

2.5.1    Compaq Insight Manager

Compaq Insight Manager is a Web-based utility that functions independently from operating environments. Compaq Insight Manager provides a consistent wrapper for SysMan and other Tru64 UNIX utilities, enabling you to manage supported systems from a Web browser -- a method of administering a computing environment that is known as Web-Based Enterprise Services (WEBES).

On a Tru64 UNIX system, you can use Compaq Insight Manager to view device details, but you must invoke SysMan Menu or SysMan Station to perform administrative tasks. On a PC or server running Windows NT, you can both view device details and invoke administrative tasks.

You can activate these Web browsing features from a dedicated HTTP port, or from the Compaq Insight Manager CIM32 or CIMXE Management Consoles running on Compaq Windows NT servers.

The Compaq Insight Manager Device homepage provides the following service icons:

2.5.2    Compaq Analyze

Compaq Analyze provides automatic background analysis of a system by constantly viewing and reading the error log file. When an event triggers an analysis rule, the analysis engine collects the error information and sends the information and analysis results to an email account determined by the system administrator.

Once Compaq Analyze is installed and configured, it starts automatically as part of the system start up procedures and runs as a background process. System administrators can start and stop the process when desired. If Compaq Analyze is already running, no new process is started, although the single, running process can support multiple graphical user interfaces for multiple users.

Compaq Analyze works in conjunction with Compaq's Web-Based Enterprise Services (WEBES.

2.5.3    Performance Manager

Performance Manager provides a passive, continuous analysis of your system to detect and correct performance problems from a central location.

Performance Manager is an optional subset of the operating system. It is a full-featured, single-system version that does not require a license. Earlier versions of Performance Manager had an optional license that enabled distributed performance monitoring and management. This license has been retired, and the product is in maintenance mode. For more information, see the Performance Manager guide.

2.5.4    Monitoring Performance History Utility

The Monitoring Performance History (MPH) utility gathers timely and accurate information on the reliability and availability of the Tru64 UNIX operating system and its hardware environment. MPH is a suite of shell scripts that copy error log and crash dump information twice per week. The information is automatically copied to Compaq for analysis through email. After analysis, reports are generated and distributed to the users of this information, namely software and hardware engineering, manufacturing, and Compaq Services. This data is internally secure to Compaq and is used exclusively for monitoring purposes.

MPH runs as a background task, using very negligible CPU resources. It is invisible to the user, requires no training to use, and does not impact or degrade system performance. For more information, see the System Administration guide.

2.5.5    The sys_check Utility

The sys_check produces an extensive dump of system performance parameters that you can use to record system values and parameters, providing a useful baseline of system data. This may be useful before you make major changes or perform troubleshooting procedures. When you run sys_check, it produces an HTML-formatted document on standard output. For more information, see the System Administration guide.

2.5.6    X-Based Utilities

Several graphical utilities are provided for fast checking of one or more aspects of system performance. These are X-based utilities that will display under any X-compliant windowing interface. In the Common Desktop Environment (CDE), these utilities are organized under the Tool Drawer icon on the CDE front panel. This icon displays the Application_Manager folder, which contains monitoring utilities in the following subfolders:

As with any graphical application, you can place the icons on the System Administration Desktop for quick access to system information or keep the displays open constantly to monitor any aspect of system performance. Programs for the graphical interfaces are located in /usr/bin/X11.

For more information, see the System Administration guide.

2.5.7    Environmental Monitoring

On any system, thermal levels can increase because of poor ventilation, overheating conditions, or fan failure. Without detection, an unscheduled shutdown could occur, causing a loss of data or damage to the system itself. Environmental Monitoring can monitor the thermal state of AlphaServer systems so that users can be alerted and the system can be shut down in an orderly manner.

The monitoring framework consists of four components: a loadable kernel module and its associated APIs, the Server System MIB subagent daemon, the envmond daemon, and the envconfig utility. For more information, see the System Administration guide.

2.5.8    Event Manager

The Event Manager (EVM), introduced in Version 5.0, provides a single point of focus for the multiple channels through which system components report event and status information. These channels include various log files, including those generated by the system logger, syslog, and the binary error logger, binlog. Each of these channels monitors some segment of the system, for example, when a disk fills, a processor begins reporting hardware errors, or whether certain routine tasks have been completed successfully.

The Event Manager combines these events into a single event stream, which the system administrator can monitor in real time or view as historical events retrieved from storage.

EVM's viewing facilities include a graphical event viewer, which is integrated with the SysMan application suite, and a full set of command line utilities, which allow administrators to filter, sort, and format events in a variety of ways.

The system administrator can also configure the Event Manager to perform automatic notification of selected conditions. Rather than replacing the familiar event channels, such as syslog and binlog, EVM encapsulates them, so these channels remain in place and continue to handle the same set of events. At the same time, EVM makes them more accessible.

EVM has the following key features:

For more information, see the System Administration guide.

2.5.9    DECevent Translation and Reporting Utility

The DECevent Translation and Reporting Utility is an error log formatting utility that translates system event log files into formatted ASCII reports. It supports both a command line and a graphical user interface.

DECevent provides two main functions:

You can have DECevent report information by event types, date, time, and event entry numbers. Reports can be selected from full disclosure to brief information messages.

For more information, see the DECevent Translation and Reporting Utility guide.

2.6    Hardware Management

In most cases, Tru64 UNIX performs hardware management automatically. However, the operating system provides tools that enable you to view device information, and to perform hardware management tasks when necessary.

2.6.1    The hwmgr utility

The hwmgr utility for hardware management, introduced in Version 5.0, helps you to manage hardware components, including disk and tape drives, processors, and buses.

The hwmgr utility offers a wide variety of options, including the following:

For more information, see the hwmgr(8) reference page.

2.6.2    Dynamic Device Recognition

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 can use DDR on SCSI devices that are unsupported by the hwmgr utility to add new devices and change existing ones. To do this, you use a utility called /sbin/ddr_config and a text database called /etc/ddr.dbase to make changes to the subsystem after installation. You do not need to reboot the system after modifying the ddr.dbase database.

DDR is preferred over the soon-to-be retired static methods of recognizing SCSI devices, because DDR will not disrupt user services and processes.

2.7    Dynamically Loadable Subsystems

Tru64 UNIX provides the ability to package, load, and manage kernel subsystems on Tru64 UNIX systems.

Instructions on how to write and package loadable device drivers so that they will install and execute on Tru64 UNIX systems are discussed in the Device Driver documentation. The Writing Kernel Modules manual explains how to write and package loadable kernel subsystems so that they will be installed and execute on Tru64 UNIX systems. The Programmer's Guide also discusses the framework that supports the dynamic configuration and tuning of kernel attributes.

2.8    Dynamic System Configuration

To simplify system tuning, Tru64 UNIX allows you to change certain kernel attributes without having to edit the system configuration file or the param.c file and without having to rebuild and reboot a target kernel for the changes to take effect. Through the use of attribute tables, each kernel subsystem -- whether a Tru64 UNIX kernel subsystem or one developed by a third-party vendor -- can define kernel attributes that can be changed at run time. You do this prior to boot time by using the /sbin/sysconfig command with the -r option (if the kernel attribute supports run-time reconfiguration). At boot time you can do this by adding or modifying entries in the kernel attribute database, /etc/sysconfigtab.

For more information, see the System Administration guide; and the System Configuration and Tuning guide.

You can also modify kernel attributes with the dxkerneltuner command; for further information, see the dxkerneltuner(8) reference page.

2.9    Dataless Management Services

Tru64 UNIX supports dataless management services (DMS), which allow the / (root), /usr, and /var partitions of a system to reside on a DMS server and to be NFS mounted over the network by a DMS client. The / and /var partitions are unique to each DMS client, while the /usr partition is shared. The DMS client swaps and dumps locally. Additional file systems can be mounted using NFS.

DMS reduces disk needs and simplifies system administration, because administrators can administer and backup their DMS clients on the DMS server.