Chapter 7. Maintaining the System
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## Chapter 7. Maintaining the System

This chapter contains these sections:

- “Managing System Information”

- “Setting System Administration Privileges”

- “Improving System Security”

- “Backing Up and Restoring”

- “Shutting Down or Restarting the System”

## Managing System Information

This section describes how to use the System Manager to manage system information. It covers these topics:

- “Overview of the System Manager”

- “Checking the Hardware Configuration”

- “Checking the Software Configuration”

- “Monitoring System Activity”

- “Setting the Time and Date”

### Overview of the System Manager

The System Manager window on your system provides access to the System Administration interactive guides described throughout this book. It also provides information about your system's hardware and software configuration, and lets you monitor your system's activity. For more information, see “Using the System Manager's Interactive Guides.”

You can also access System Manager windows for other systems on the network to view their system information, to access their shared resources, and to log in. For information, see the Desktop User's Guide .

### Checking the Hardware Configuration

You use the “About This System” item in the lefthand column of the System Manager window to check your system's hardware configuration. The “About This System” window displays the following information:

- workstation name

- model

- serial number

- IP address

- processor speed

- operating system

- main memory

- caches (if present)

The window also includes items that you can click to find out additional information about the system's hardware configuration.

- “Audio” displays the type of audio hardware installed on the system.

- “CPU” displays the type, speed, and version of your system's central processing unit (CPU). If you have more than one CPU, the “CPU” choice has a rollover menu that lists all CPUs.

- “Graphics” displays the type of graphics hardware installed on the system.

- “Video” displays the type of video hardware installed on the system.

- “SCSI” displays a list of all the valid SCSI addresses on the system and the devices using those address.

#### Checking Disk Information

You can view information about disks connected to your workstation using the Disk Manager. Choose System Manager from the System toolchest, select the Hardware and Devices category, and then click “Disk Manager.” A window appears and displays information about the disks currently mounted on your system. For more detailed information about a disk, select it in the window and click the Get Info button.

#### Checking Removable Media Device Information

To find out information about removable media devices on your system, such as tape, CD-ROM, floppy, floptical, or SyQuest drives, use the Removable Media Manager, also available in the Hardware and Devices category in the System Manager. To view information about a specific device, select it in the Removable Media Manager window, and click the Get Info button.

#### About SCSI Devices, Controllers, and Addresses

You can connect several Small Computer System Interface (SCSI) devices, such as hard disks, tape drives, floppy drives, and printers, to your system. Your system has at least one SCSI controller (an internal board that sends data to and from the devices). The SCSI controller to which your system disk is connected has an ID number of 0. Each SCSI controller can support up to seven devices.

The instructions that come with each SCSI device show you how to physically set its address; your system's owner's guide shows you how to connect the device to the SCSI port, and how to daisy-chain several SCSI devices together.

To check the available SCSI addresses, click “SCSI” in the “About This System” window. (To open the window, choose System Manager from the System toolchest and click “About This System.”) You can find out the type, controller, and address of each SCSI device that is connected to the system.

### Checking the Software Configuration

To view a list of all installed software products, select the Software category in the System Manager window and then click “List Installed Products.” A guide appears and lets you open the Software Manager. The Software Manager automatically displays the products currently installed on the system.

You can use the Software Manager to remove an existing product or to install a new product. See “Installing Software” for more information.

### Monitoring System Activity

The System Manager provides several graphical tools that display the changing activity levels of your system. Select the System Performance category. You see the following items:

- View the System Log

  The System Log is where information about important events that occur on the system are recorded. These include messages about system errors and possible security problems.

- View the System Administration Log

  The System Administration Log is where actions taken on the system, as well as warning and error messages, are recorded.

- Set System Admin Log Options

  This guide lets you set preferences for how information is recorded and displayed in the System Administration Log.

### Setting the Time and Date

Once you set the date and time, the system can accurately stamp the time of events, such as when you last changed a file. On most networks, the current date and time are periodically provided to all workstations on the network.

You set the date and time with the IRIX `date` command, which has this format:

`date [``mmddhhmm[yy]``]`

mm specifies the month, dd the day, hh the hour, and mm the minutes. You can also specify the last two digits of a year (yy). For more information and options, see the `date` reference (man) page.

To set the date and time, follow these steps:

1. Log in as root through a shell window.

   - Choose “Open Unix Shell” from the Desktop toolchest.

   - Position your cursor within the new window and type

     `login root`

     Then press `<Enter>`.

     If a prompt for a password appears, type the password and press `<Enter>`. If a prompt appears but the root account has no password, just press `<Enter>`.

2. Check the current time and date of the system by typing

   `date`

   Then press `<Enter>`.

3. Specify the date and time. For example, if today is March 17 (0317) at 2:30 p.m. (1430) in the year 1992 (92), type

   `date 0317143092`

   Then press `<Enter>`.

4. To check the date and time, type

   `date`

   Then press `<Enter>`. You see a line similar to this:

   `Tue Mar 17 14:30 1992`

5. Log out of the root account by typing

   `logout`

   Then press `<Enter>`. The shell window disappears.

## Setting System Administration Privileges

The Privilege Manager and related guides let you, as the Administrator of your system, determine whether other users on the system will be able to perform system administration tasks. You do this by enabling privileges on your system and then assigning privileges, either all of them or selected ones, to individual users. You can also delete privileges for individual users or disable privileges for the entire system (this prevents any user but the Administrator from performing system administration tasks).

| Note: If the root account on your system does not have a password, privileges are enabled by default. This means that any user on the system can perform system administration tasks.

To open the Privilege Manager, choose System Manager from the System toolchest, select the Security and Access Control category, and then click “Privilege Manager.”

### About Default Privileges

By enabling privileges on your system, you assign a set of default privileges to all the users on the system. These default privileges allow users to view information about the system.

### Overview of the Privilege Manager

When you open the Privilege Manager, you see the currently assigned privileges on the system. (If the window is empty, it means that the root account does not have a password or that you haven't enabled privileges on the system.)

The Task menu contains these choices:

- “Grant Privileges to a User” opens the “Grant Privileges to a User” guide, which allows you to assign all or selected privileges to individual users. This command is equivalent to the Grant button. See “Granting Privileges to Users” for information.

- “Revoke Privileges from a User” lets you remove selected privileges from individual users. This command is equivalent to the Revoke button. See “Revoking Privileges from Users” for information.

- “Enable Use of Granted Privileges” allows you to enable users who have bee granted privileges to use them. This command is equivalent to the Enable button. See “Enabling Privileges” for information.

- “Disable Use of Granted Privileges” lets you prevent users from using privileges that they may have previously been granted. The command prevents any user except the Administrator from performing system administration tasks. This command is equivalent to the Disable button. See “Disabling Privileges” for information.

- “System Manager” opens the System Manager window, which gives you access to all of the system administration interactive guides.

- “Close” closes the Privilege Manager window. Any changes you made using the guides are saved. This command is equivalent to the Close button.

The View menu contains these choices:

- “By User” lists the privileges for each user account on the system. It also lists the privileges available to all users on the system; see “About Default Privileges” for more information.

- “By Privilege” lists each privilege available on the system and then includes the names of the users on the system who have been assigned the privilege. It also lists whether a privilege is a default privilege and thus automatically assigned to every user on the system; see “About Default Privileges” for more information.

- “By Task” lists privileges according to the individual tasks that require them. For example, to use the “Add an Outgoing PPP Connection” task, a user must be assigned the “Add Outgoing PPP” and “Test PPP Outgoing Existence” privileges.

| Note: Be aware that some tasks have more than privilege associated with them. If you want to allow a user to perform a specific task, you must assign the user all the necessary privileges associated with that task. To view the privileges for each task, choose “By Task” from the View menu.

The View menu also includes the following options for viewing privileges:

- “Hide Users With No Privileges” means that only user accounts that have been assigned privileges appear in the Privilege Manager window. This includes “All Users,” which is used to display the default privileges.

- “Hide Unused Privileges” displays default privileges and those privileges that have explicitly been assigned to a user or users. It does not display other privileges that haven't otherwise been assigned (either by default or explicitly).

- “Hide Default Privileges” shows only the privileges that have explicitly been assigned to a specific user. It does not show any of the default privileges that are automatically assigned to other users when you enable privileges.

- “Use Descriptive Privilege Labels” lists the tasks and privileges by their descriptive names.

The Help menu contains a list of help topics. To view a topic, choose it from this menu.

### Granting Privileges to Users

You can give individual users the ability to perform specific system administration tasks by using the “Grant Privileges to a User” guide. For example, you may want the user “joe” to be able to add a modem to the system and create an outgoing PPP connection. To allow “joe” to perform these tasks, you use the “Grant Privileges to a User” guide and grant privileges on a task basis, selecting “Add a Modem” and “Add an Outgoing PPP Connection” on the appropriate page in the guide.

You can open the “Grant Privileges to a User” guide using one of these methods:

- Choose System Manager from the System toolchest. Select the Security and Access Control category and click “Privilege Manager.” In the Privilege Manager window, click the Grant button. The guide appears and leads you through the necessary steps.

- Choose System Manager from the System toolchest. Select the Security and Access Control category and click “Grant Privileges to a User.” The guide appears and leads you through the necessary steps.

### Revoking Privileges from Users

You can revoke privileges that you previously assigned to a user by using the “Revoke Privileges from a User” guide.

You can open the “Revoke Privileges from a User” guide using one of these methods:

- Choose System Manager from the System toolchest. Select the Security and Access Control category and click “Privilege Manager.” In the Privilege Manager window, click the Revoke button. The guide appears and leads you through the necessary steps.

- Choose System Manager from the System toolchest. Select the Security and Access Control category and click “Revoke Privileges from a User.” The guide appears and leads you through the necessary steps.

### Enabling Privileges

You can open the “Enable Use of Granted Privileges” guide using one of these methods:

- Choose System Manager from the System toolchest. Select the Security and Access Control category and click “Privilege Manager.” In the Privilege Manager window, click the Enable button. The guide appears and leads you through the necessary steps.

- Choose System Manager from the System toolchest. Select the Security and Access Control category and click “Enable Use of Granted Privileges.” The guide appears and leads you through the necessary steps.

### Disabling Privileges

You can open the “Disable Use of Granted Privileges” guide using one of these methods:

- Choose System Manager from the System toolchest. Select the Security and Access Control category and click “Privilege Manager.” In the Privilege Manager window, click the Disable button. The guide appears and leads you through the necessary steps.

- Choose System Manager from the System toolchest. Select the Security and Access Control category and click “Disable Use of Granted Privileges.” The guide appears and leads you through the necessary steps.

## Improving System Security

The System Manager provides several options to help you, as the Administrator for your system, improve the system's security. In general, improving security means controlling and limiting access to the system by other users, including local users or users on remote systems on the network.

The “Improve System Security” guide lets you make the following settings:

- Assign a password to the root account, if it doesn't already have one.

  The most important method for improving security is creating a password for the root account. If the root account does not have a password, any person can log in to the root account and deliberately or accidently destroy files or directories that are essential for the system to operate.

  | Note: Make sure you remember the root password. The system does not provide a way to log into the root account without its password.

- Assign passwords to each active user account on the system or lock unused accounts to prevent unauthorized people from logging in.

  For active user accounts (accounts that people are currently using), you can either consult each user to find out their preferred password or simply assign them a password and then let them change it later using the “Modify My Account Password” guide (available in the User Manager). For user accounts that aren't currently being used, you can lock them to prevent unauthorized people from trying to use the accounts to log in to the system.

- Disable Java or JavaScript for each user account, including the root account.

  Java and JavaScript are commonly used programs that support certain features of the World Wide Web. When you use a browser to visit a Web site, your system can download and run a Java program without you being aware of it. Once on your system, the program has access to and can corrupt your files and directories. By disabling Java and JavaScript for a user account, you prevent this type of access.

  | Note: If the root account on the system does not have a password, your system is particularly vulnerable to Java and JavaScript programs. Make sure you either assign a password to the root account or disable Java and JavaScript for the root account.

- Disable logins to NIS accounts.

  When you create a user account on the system, you have the option of creating a network access account if the system is connected to a network and if NIS is being used on that network. (See “Creating a User Login Account.”) Users on the network can use those NIS accounts to log in to your system if NIS is turned on. If you want to limit access to your system to local users only, you can disable logins to NIS accounts.

- Use shadow passwords.

  When you create passwords for user accounts on the system, the system encrypts the passwords and places them in a special file. Any user on the system can view the file and see the encrypted passwords. This gives a user the opportunity to possibly decipher the passwords, thereby gaining unauthorized access to another user's account. To prevent any user but root from viewing the password file, you can have the system use a shadow password file.

- Require passwords at login.

  By requiring passwords, you can ensure that unauthorized people can't gain access to the system using an open user account. An open user account is an account that is neither locked nor has a password assigned to it. (As a rule, it's a good idea to either lock an account or assign a password to it.)

- Disable the Visual Login Screen.

  When you start up your workstation, by default you see a login screen with the names of all the user accounts on the system. (You may also see photographs representing user accounts, depending on how users customize their accounts.) By displaying information about the users, the login screen may provide information that unauthorized people can use to gain access to one or more of the user accounts. To prevent this from happening, you can disable the Visual Login Screen.

- Disable privileged users.

  The Privilege Manager, available in the System Manager, allows the Administrator to assign selected privileges, normally assigned only to the root user, to other users on the system. Depending on the privileges assigned, these other users may be able to affect essential operations of the system. To prevent this from happening, you can disable privileged users from being able to log in to the system.

- Protect new users' files.

  This setting means that when you create a new user account on the system, the account's files are protected from other users on the system. Other users can view the account's files but only the owner of the account can make changes to the files.

- Disable remote display.

  By disabling remote display, you prevent applications running on remote systems from being able to display on your system's screen.

- Disable IP forwarding.

  IP forwarding allows systems on a network to share information, such as hostnames and IP addresses, about one another. Unauthorized people may be able to use this information to breach the security of systems on the network. To prevent your system from sharing information about itself with other systems, you can disable IP forwarding.

To open the “Improve System Security” guide, open the System Manager (if it isn't already open), select the Security and Access Control category, and click “Improve System Security.”

## Backing Up and Restoring

This section contains the following information:

- “Developing a Backup Strategy” explains how to make a schedule for regular backups and describes how to select the right kind of tape on which to make your backup.

- “Overview of the Backup and Restore Manager” describes what each guide does, how to start it, and explains how to use the guides to back up your system's files.

- “About Tape Formats and Capacities” describes the different available formats and discusses compatibility issues.

- “Backing Up Files” explains how to perform and schedule a backup of files on your system.

- “Restoring Files From a Backup” explains how to restore files to your system from a previous backup.

- “Unscheduling a Backup” describes how to unschedule a previously created backup.

- “Using Other Tools to Back Up and Restore Files” describes other standard IRIX tools for backing up and restoring information. It also explains how to use the IRIX `tar` utility.

### Developing a Backup Strategy

The first step toward ensuring the safety of your system's information is to develop a backup strategy. You should plan on performing incremental backups each day and backing up the entire system at least once a week. See your network administrator to coordinate your backup strategy with the overall scheme of network backups.

| Note: Always make a new backup of the entire system after you work on user accounts, add devices, or install new software. Only a full system backup can completely restore your system in the event of a serious system software failure. If a system failure occurs, customized system information will be lost.

Make sure all users agree to and are aware of the set time for the weekly backup. Try to schedule it for a time when the system is not usually being used, such as early on Monday morning or late Friday afternoon.

Always use at least two sets of backup tapes between which you alternate the weekly backup. When you start a backup, the system copies this new information over the old, which effectively deletes the old information. If you use last week's backup tape to perform this week's backup, you run the risk of having a system failure when the tape contains some combination of new and old information.

Finally, the tape drive is an option on the system. If you do not have a tape drive, you can back up your system using the tape drive of another system that is part of your network.

### Overview of the Backup and Restore Manager

The Backup and Restore Manager provides access to several guides that you use in combination to back up and restore the entire contents of a disk or selected directories and files and onto a tape or disk. The tape can be located in either a local tape drive (one that is physically connected to your system) or a remote tape drive (one that is physically connected to another system on the network). The Backup and Restore Manager also displays information about the backups that you create, including the name of the backup, the location where the backed up files will be stored, the user who created the backup, and when and how often the backup will be performed.

To open the Backup and Restore Manager, select the Files and Data category in the System Manager and then click “Backup and Restore Manager. (To open the System Manager, choose System Manager from the System toolchest or click the words “System Manager.”)

You can use the Get Info button in the Backup and Restore Manager window to display detailed information about a specific backup. Select the name of the backup in the window and click Get Info. A Schedule Backup Info window appears and displays the file(s) that are included in the backup, as well as other information about the backup.

#### About the Menus

The Task menu contains these choices:

- “Schedule Backup” opens the “Back Up Files” guide, which lets you perform a backup (after completing the guide) or schedule a backup for a later date. The guide lets you choose between performing a full system backup or selecting specific files or directories to back up. This command is equivalent to the Backup button. See “Backing Up Files” for more information.

- “Restore Files” opens the “Restore Files From Backup” guide, which lets you restore files to your system from a previous backup. This command is equivalent to the Restore button. See “Restoring Files From a Backup” for more information.

- “Unschedule Backup” opens the “Unschedule a Backup” guide, which gives you the opportunity to cancel a previously scheduled backup. This command is equivalent to the Unschedule button. See “Unscheduling a Backup” for more information.

- “System Manager” opens the System Manager window, which gives you access to all of the system administration interactive guides.

- “Close” closes the Backup and Restore Manager window. Any changes you made using the guides are saved. This command is equivalent to the Close button.

The Help menu contains a list of help topics. To view a topic, choose it from this menu.

| Note: As an alternative to the backup and restore guides, you may want to use a IRIX utility called `bru`. For more information on `bru`, see “Using Other Tools to Back Up and Restore Files.”

### About Tape Formats and Capacities

Silicon Graphics supports a number of different 8mm and DLT drives, including the 8505XL and 2000XL drives, as well as several of the more high-end tape drives.

Third-party drives are not directly supported; see the file `/var/sysgen/master.d/scsi` for information about configuring third-party drives.

When you purchase additional tapes, be sure to specify the type of drive you have. To check which type you have, open the Removable Media Manager (available in the Hardware and Devices category in the System Manager). See “About the Menus” for more information.

You also insert and lock tapes into the drive differently depending on the type of drive. See the installation guide included with the drive or your system owner's guide for this information.

| Note: Silicon Graphics no longer ships QIC drives but it does still provide support for them.

### Backing Up Files

You use the “Back Up Files” guide to back up files on your system. You can access the guide in one of these ways:

- In the System Manager, select the Files and Data category, and click “Back Up Files.”

- In the System Manager, select the Files and Data category, click “Backup and Restore Manager,” and then click the Backup button.

Before using the “Back Up Files” guide, you should consider the following issues:

- Do you want to perform a full system backup or selected backup?

  - A full system backup requires the root password. For this reason, the Administrator typically performs full system backups to back up all the files on the system.

  - You do not need to know the root password to back up selected files and directories that you own. If you try to back up files that you do not have permission to view (read), the system won't back up those files.

- Do you want to perform the backup now, later, or on a recurring basis?

  - “Now” means that the system will begin backing up files when you click the OK button on the last page of the guide.

  - “Later” means that the system will perform the backup at the time and date (in the future) that you specify. You specify the date of the backup by selecting a date some number of days in the future. For example, if the current date is July 25 and you want the backup to occur on July 30, then you would enter “5” in the field labeled “Days from today.”

  - “Recurring” means that the system will regularly perform the backup on a daily or weekly basis. For example, you can set the backup to occur every Friday at 5:00 pm. Or, you can set the backup to occur every day at midnight.

- Where do you want to store the backed up files?

  - If you want to store the files on a tape, make sure that you have a tape drive connected to your system or that you have access to a remote tape drive connected to another system on the network.

    | Note: If an existing Ethernet network is available, follow the instructions in “Setting Up Network Connections” to put your system on a network where you can access a remote tape drive. If there is no network available, contact the system's manufacturer to order a tape drive for your system.

  - To store the files on a disk, make sure you have enough disk space available. (You can use the Filesystem Manager to view available disk space.) You need to specify the full path name of the file in which you want to store the backed up files. For example, `/usr/people/benjamin/backup.7.25`.

### Restoring Files From a Backup

If you accidentally remove a file or directory, or something goes wrong with the system, you can restore your files and information from a backup tape or a backup file. (You can also restore an old version of a file.) If you're backing up from a tape, make sure you have the most recent backup tape when you restore files. If you're backing up from a file, make sure you know the name and location of the file on your system.

If you do not have a local tape drive, you can restore files using a tape drive connected to a remote system on the network. If possible, use the same remote tape drive to back up and restore information. That way you'll be sure the drive can read your backup tape. (For more information on tape formats, see “About Tape Formats and Capacities.”)

Users can restore files that they own, but only the Administrator can restore an entire system.

| Caution: If you restore files to a directory in which files of the same name exist, the files on the hard disk will be replaced with the files from the tape.

| Note: In the event of a serious system failure, you may need to restore the entire operating system. See your owner's guide or IRIX Admin: Backup, Security, and Accounting .

To restore a file or filesystem, open the “Restore Files From Backup” guide, available in the Files and Data category in the System Manager. A guide appears and leads you through the necessary steps.

After you finish restoring your files from tape, remove your tape from the drive and store it in a safe place.

### Unscheduling a Backup

You may decide at some point that you don't want the system to perform a backup that you previously scheduled. To remove a backup from the list of scheduled backups, open the “Unschedule a Backup” guide, available in the Files and Data category in the System Manager. A guide appears and leads you through the necessary steps.

Once you unschedule a backup, it no longer appears in the Backup and Restore Manager. If you want to back up the same files again, you need to use the “Back Up Files” guide to create and schedule another backup.

| Note: If the backup you want to unschedule was created by the Administrator, you must have the necessary privileges or know the root password in order to unschedule it. For information about privileges, see “Enabling Privileges.”

### Using Other Tools to Back Up and Restore Files

IRIX provides several tools for backing up and restoring files. This section describes each tool and shows you how to use `tar`, one of the most widely used tools.

The tools described in this section come standard on every system.

`bru` |  | `bru` (backup/restore utility) can back up and restore an entire filesystem or individual directories and files. It can compress and decompress files, find and back up files based on modification date, check space requirements, and verify whether a backup was successful. See the `bru(1)` reference (man) page for more information.
`tar` |  | `tar` (tape archiver) backs up specific files and directories. You can copy files to tape, create `tar` files, compare files on tape to files on disk, read standard input, and pipe the output of `tar` to other processes. See also “About tar.” See the `tar(1)` reference (man) page for more information.
`cpio` |  | Like `tar`, `cpio` (copy in/out) archives files and directories. With `cpio` you can copy files to tapes or disks, archive empty directories, swap byte order, create portable ASCII archives, and read from and write to standard output. See the `cpio(1)` reference (man) page for more information.
`dump/restore` |  | `dump` and `restore` are standard filesystem backup and restore utilities available on most UNIX systems. `dump` makes incremental backups of entire filesystems; `restore` retrieves files from archives created by `dump`. `restore` can restore an entire filesystem or individual files and lets you browse the contents of an archive and select specific files for restoration. For more information, see the reference (man) pages for `dump(1M)` and `restore(1M)`.

#### About tar

`tar` is a very portable, general-purpose backup and restore tool. Most systems that run the UNIX operating system support `tar`. This section gives you a brief introduction to using the basic features of `tar`. For more information, see the reference (man) page for `tar`.

Only the owner of a directory or file can back it up with `tar`. You must be logged in as root if you're backing up files that belong to multiple users.

#### Copying Files to a Tape With tar

To copy files to a tape in a local or remote drive, follow these steps:

1. Open a shell window by choosing “Open Unix Shell” from the Desktop toolchest.

   To back up files that are owned by several different users, log in as root by typing:

   `login root`

   Then press `<Enter>`.

   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>`.

2. Make sure that a tape is in the tape drive. (See “About Tape Formats and Capacities” to make sure you have the correct type of tape for your drive.)

3. Run the `tar` command.

   The command has this format:

   `tar` options device pathname

   options are letters that describe how you want to use `tar`; for example, `c` specifies copy to tape, and `v` (for “verbose”) specifies that `tar` should list the files while copying them. device is the name and location of the tape drive; you do not need to specify the device when you're copying to the default local drive. pathname is the full pathname of a file or directory.

   - To copy the `/usr/charts` directory to a tape in a local drive and to view the contents of the directory while it's being copied, type

     `tar cv /usr/charts`

     Then press `<Enter>`. `tar` replaces any information on the tape with the contents of the `/usr/charts` directory.

   - To copy the same directory to a tape in a remote drive, add the `f` option before the tape device name (the device name consists of a login name, remote hostname, and device file, which is usually `/dev/tape`). To copy `/usr/charts` to the tape drive connected to the system mars through the guest account, type

     `tar cvf guest@mars:/dev/tape /usr/charts`

     Then press `<Enter>`.

     | Note: This example uses the guest account because it usually does not have an associated password. If yours is a very secure environment, this account may have a password. If so, work with the Administrator of the remote system or the network administrator to set up an account through which you can access the drive.

     While `tar` copies the directory, you see a listing similar to this:

         a /usr/charts/north 83 blocks
         a /usr/charts/south 102 blocks
         a /usr/charts/east 124 blocks
         a /usr/charts/west 86 blocks

     To stop the copy, press `<Ctrl-C>`. The copy is complete when you see the system prompt.

#### Viewing the Contents of a Tape Using tar

To view the contents of a tape created with `tar`, follow these steps:

1. Open a shell window by choosing “Open Unix Shell” from the Desktop toolchest.

2. Insert the tape in the drive.

3. Position your cursor in the shell window and issue the `tar` command.

   - To list the contents of a tape in a local drive, type:

     `tar tv`

     Then press `<Enter>`.

   - To list the contents of a tape in a remote drive; for example, for the drive connected to the system `mars`, type

     `tar tvf guest@mars:/dev/tape`

     Then press `<Enter>`.

         rwxr-xr-x  dir     Feb 11 08:41 1992   /usr/charts
         rwxr-xr-x  42004   Feb 11 08:41 1992   /usr/charts/north
         rwxr-xr-x  51869   Feb 11 08:41 1992   /usr/charts/south
         rwxr-xr-x  63217   Feb 11 08:41 1992   /usr/charts/east
         rwxr-xr-x  43554   Feb 11 08:41 1992   /usr/charts/west

     To stop the listing, press `<Ctrl-C>`. The listing is complete when you see the system prompt.

#### Restoring Files From a Tape Using tar

To copy files onto your disk that you previously archived to tape using `tar`, follow these steps:

1. Open a shell window by choosing “Open Unix Shell” from the Desktop toolchest.

   To restore files that are owned by several different users, log in as root by typing

   `login root`

   Then press `<Enter>`.

   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>`.

2. Compare the contents of the directory to which you want to restore the files with the contents of the tape.

   | Caution: If files on the tape have the same name as files in the directory to which you are restoring files, the files on your hard disk will be replaced by the files on the tape.

   - View the contents of the directory (for example, `/usr/charts`) by typing

     `ls -al /usr/charts`

     Then press `<Enter>`.

   - View the contents of the tape using the appropriate command from “Viewing the Contents of a Tape Using tar.”

   - Look for files in the directory that have the same names as files on the tape. If you do not want the files on the tape to replace those of the same name on your hard disk, you may want to rename or move the files on the hard disk.

3. Position your cursor in the shell window and issue the `tar` command with the `x` (for “extract”) option.

   - To restore the entire contents of a tape in a local drive to its original location on your hard disk, type

     `tar xv`

     Then press `<Enter>`.

   - To restore a specific file or directory (for example, `/usr/charts/north`) from a tape in a local drive to its original location on your hard disk, type

     `tar xv /usr/charts/north`

     Then press `<Enter>`.

   - To restore a specific file or directory (for example, `/usr/charts/north`) from a tape in a local drive to a different location on your hard disk (for example, `/usr/tmp`), type

     `cd /usr/tmp;tar xvR /usr/charts/north`

     Then press `<Enter>`. The name of this file is now `/usr/tmp/usr/charts/north`.

   - To restore the entire contents of a tape in a remote drive (for example, the drive connected to the system `mars`) to its original location on your hard disk, type

     `tar xvf guest@mars:/dev/tape`

     Then press `<Enter>`.

   - To restore a specific file or directory (for example, `/usr/charts/north`) to its original location on your hard disk, type

     `tar xv guest@mars:/dev/tape /usr/charts/north`

     Then press `<Enter>`.

   - To restore a specific file or directory (for example, `/usr/charts/north`) from a tape in a remote drive to a different location on your hard disk (for example, `/usr/tmp`), type

     `cd /usr/tmp;tar xvR guest@mars:/dev/tape /usr/charts/north`

     Then press `<Enter>`. The name of this file is now `/usr/tmp/usr/charts/north`.

     While `tar` restores the file(s), you see a listing similar to this:

         x /usr/charts/north, 42004 bytes, 83 blocks
         x /usr/charts/south, 51869 bytes, 102 blocks
         x /usr/charts/east, 63217 bytes, 124 blocks
         x /usr/charts/west, 43554 bytes, 86 blocks

     The restoration is complete when you see the system prompt.

   To stop the restoration, press `<Ctrl-C>`. For more information on the `tar` command and its options, see the reference (man) page for `tar`.

## Managing Processes

IRIX is a multi-tasking operating system. This means that your system can perform many operations simultaneously. For example, you can run an application, print a file, and read your mail at the same time, without having to wait for each operation to complete before beginning the next one.

Every program that you run on the system is assigned a process ID that allows IRIX to keep track of what it is doing. By identifying the process numbers assigned to tasks, you can manage your operations more effectively.

### About Processes

When you are working at your system, the IRIX process that you are currently working with, either from the keyboard or with the mouse, is known as the foreground process. Any other IRIX processes running on the system are known as background processes.

### Monitoring Processes

While many of the processes you are performing may be readily identifiable from your desktop, many others, including printing and some complex graphics operations, may be hidden from you. To identify quickly all the processes running on your system, you can enter the IRIX `ps` (processor status) command in an IRIX shell.

To monitor processes, follow these steps:

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

2. Position your cursor within the shell window and type

   `ps -a`

   Then press `<Enter>`.

   When you enter the `ps -a` command, IRIX lists a process ID number (PID), a terminal ID (TTY), time, and name of each process that you started on your system; it does not show all running processes. For example:

       PID     TTY    TIME    COMMAND
       7662    ttyq1  4:54    csh
       7668    ttyq1  15:04   ps
       7670    ttyq1  15:14   cedit

   To check all running processes for a specific process, such as `dmb`, type

   `ps -ef | grep dmb`

   Additional parameters in the `ps` command line provide more comprehensive listings. For more information on the command, see the man page for `ps`.

### Stopping Processes

Occasionally you may want to stop a process—for example, a PostScript® printing process that measurably slows down system operations. In many cases, you can use an application command to stop a process from the desktop. But in some instances, you must stop the process from the shell by using the `kill` command. A regular user can use the command to kill only his or her own processes; the Administrator can stop any process running on the system.

| Note: If a system process is stopped by the Administrator, the termination may cause the system to hang or crash. Always save your current work before stopping a system process as the Administrator.

To stop a process, follow these steps:

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

   To stop a process started by the Administrator, or to stop processes started by several different users, log in as root by typing

   `login root`

   Then press `<Enter>`.

   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>`.

2. Position your cursor within the new window and type

   `ps -ef`

   Then press `<Enter>`.

   The listing provides a full listing, including the process ID (PID), of all processes that are currently running. Find the one that you want to terminate.

3. Use the `kill` command with the PID as the parameter. For example, to kill process number 754, type:

   `kill 754`

   Then press `<Enter>`.

   Additional parameters in the `kill` command line provide variations on process terminations. For example, the command `kill -9` is a “sure-kill,” stopping almost any type of process. For more information on the `kill` command, see the reference (man) page for `kill`.

## Shutting Down or Restarting the System

### Shutting Down the System

When you shut down the system, the IRIX operating system closes down all processes and files in a specific order so that no information is lost. You should always close your own files and stop running applications before you shut down the system.

To shut down the system, follow these steps:

1. Choose “System Shutdown” from the System toolchest.

2. The “System Shutdown” guide appears with several options available, depending on the type of workstation you have.

   - If your workstation does not have the ability to automatically power off, no options appear in the notifier; click the OK button to continue the shutdown, then turn off the workstation when you see the message that says the workstation is ready to be powered off.

   - If your workstation can power off automatically, you can choose to have it do so, and choose to have it automatically power on at a certain time. After you set the options, click the OK button continue the shutdown.

### Restarting the System

When you restart the system, the IRIX operating system closes down all processes and files in a specific order so that no information is lost, then it restarts the system.

You should always close your own files and stop running applications before you restart the system.

To restart the system, choose “Restart System” from the System toolchest.

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Chapter 6. Managing Disks and Filesystems |  | Chapter 8. Troubleshooting