CHAPTER 1: GETTING STARTED
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The MMM Division's computing environment supports many users on several different computing hardware platforms, each functioning somewhat differently. This introductory chapter provides some basic information needed to begin working in MMM's computing environment:

1.1 Preliminary Information

1.1.1 Getting an Account

All MMM staff, visitors, and students are eligible for an account on the divisional computing systems. To obtain an account, you must first complete a computing information form, available from the MMM Systems Manager, Pat Waukau, the Computing Assistant, Jose Castilleja, or the Visitor Coordinator, Sudie Kelly. In addition, the Account Request Form is available from our website.

1.1.2 Introduction to the MMM Computing Environment

The MMM computing environment consists of the following Unix architectures: Sun, HP Alpha, SGI, and Linux on Intel platforms. There is a central file server (oak) and data server (hop) for these systems.  Users do not have login access to the file server.  The user file systems and a variety of software packages are available from the file server.  Users do have login access to the data server.  These file systems are then served to the divisional systems across a switched ethernet network.

Users have login access to several general-use Sun, HP Alpha, SGI, and Intel Linux, workstations. Additional information on the division's workstations and their availability is located at the Computing Resources page.

MMM staff are allotted a 500MB (megabyte) disk quota for permanent file storage on the file server (oak) and visitors are allotted 200MB. Files on the permanent storage disk are backed up biweekly by the systems staff, early Tuesday and Friday mornings.

Users also have access to temporary (volatile) file storage (up to 3GB) on /mmmtmp. This disk is physically connected to the data server (hop). This disk is purged nightly with a scrubbing algorithm that deletes all files older than four days. There are also three longer term storage disks, which have a 21 day scrubber and a user quota of 4GB (datatmp1, datatmp2, and datatmp3). Access to these disks can be acquired by submitting an assist request. Files on /mmmtmp and the longer term data disks are not backed up. In addition, each science group has a 9GB allocation on the data server hop. The data disks are automounted to all of the divisional desktop workstations.  The quota system set up on this system is based on Group Identifiers (GID).  Each section within the division has been assigned a GID.  Management of this space is the responsibility of the individual groups.

The MMM computing environment consists of several different hardware platforms that each require a slightly different procedure to log on and off. This introductory chapter will explain how to log on and off workstations from the workstation consoles.


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1.2 Logging On and Off

1.2.1 HP Alpha Workstation Console

To Log onto a HP Alpha Workstation at the Console

The default interface is the Common Desktop Environment (CDE).

  1. Enter username in the window.
    Press RETURN.

  2. Enter password in the window.
    Press RETURN.

To Log Off

  1. Exit from windows. Or move cursor to the window background, click the left mouse button, drag the cursor to the logout option.

1.2.2 Sun Workstation Console

There are two different ways for logging onto Sun workstations, depending on whether the system is configured to use the Common Desktop Environment (CDE) or the Sun OpenWindows environment.

To log onto a Sun Workstation at the Console running CDE (Recommended)

The default interface is the Common Desktop Environment (CDE).

  1. Enter username in the window.
    Press RETURN.

  2. Enter password in the window.
    Press RETURN.

To Log Off

  1. Exit from windows. Or move cursor to the window background, click the left mouse button, drag the window to the logout option.

To Log onto a Sun Workstation at the Console not running CDE

  1. At the login prompt, type your username
    and press RETURN.
  2. At the password prompt, enter your password
    (the characters you enter for the password will not
    show up on the screen) and press RETURN.

Note: The workstation is now in "dumb-terminal" mode. It is not recommended that a workstation console be used in this mode. Instead, use the X Window System (described below).

To Activate X Window Applications

  1. At the prompt, type startx and press RETURN. X applications
    specified in your .xinitrc or .xsession files are started. See
    Chapter 10 for more information on these files.

Note: If this procedure does not work, the proper information may not be included in your .mwmrc file. In addition, there are other window systems, such as OpenWindows, that run on the Sun workstations. For more information, see Chapter 10 on window environments.

To Deactivate the Window Manager and Log Off

  1. Type exit at the prompt to deactivate the X Window applications
    and return to "dumb-terminal" mode. The screen will clear, and the
    prompt will return. This is the default behavior of the .xinitrc file
    in /usr/local/skel. Other .xinitrc files may require different
    actions to remove X Window applications.
  2. At the prompt, type exit again to log off entirely.

1.2.3 SGI Workstation Console

To Log onto an SGI Workstation at the Console

  1. At the Username prompt, type your username
    and press RETURN, or double-click on your user icon.
  2. At the password prompt, enter your password (the characters you
    enter for the password will not show up on the screen), then
    either press RETURN or click on the login button.

The X Window system will activate automatically according to information contained in the .xsession file. If you do not have a .xsession file, a menu and console icon will be displayed to the screen. Double-click on the console icon and start up an X terminal from there.

To Log Off

  1. Type exit from your window, or click on System
    from the menu and select Logout.

You may receive a message on the screen asking you to confirm that you want to log out.

1.2.4 Intel Linux Console

The default interface for the Linux systems is KDE. To Log onto an Intel Linux workstation at the Console

  1. Enter username in the window.
    Press RETURN.

  2. Enter password in the window.
    Press RETURN.

To Log Off

  1. Move cursor to the window background, click the left mouse button, drag the cursor to the logout option.


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1.3 Custom Environments

There are a number of special files that allow you to customize your Unix environment.  These files, often called "dot files" because their filenames begin with a period (.), are located in your login (main) directory and have specific names that should not be changed.  These files include .cshrc, .login, .profile, and .logout.  This section will discuss these files, and how to customize your shell environment and general login environment.  These samples have some basic branching code to work effectively among multiple architectures.  Sample versions of these files are found in the directory /usr/common/skel.

1.3.1 .cshrc file

When you log into an MMM workstation, the default shell (command interpreter) is the C-shell. Every time a process (command) is started, the shell program reads a file called .cshrc in your home directory.  This file contains instructions that define the C-shell environment, and can contain shell commands that you would enter on the command line.  It is subsequently called prior to executing other commands that are not built into the shell, such as ctrans or dotex.  You can customize parts of your shell by adding or changing commands in the .cshrc file.  Commands typically placed in the .cshrc file are those specifying directory paths, shell variables, and aliases.  It is best not to add excessive instructions to the .cshrc because it slows down the execution of commands.  You are also cautioned against using any commands that echo output in the .cshrc; certain applications will accept these characters as input, which may cause them to malfunction.  In addition, do not define aliases that are the same as Unix commands.  See Chapter 2 for additional information on aliases.

1.3.2 .login file

When you log in to a system, the C-shell executes commands in the .login file after executing the .cshrc file. Unlike the .cshrc file, the .login file is read only once when you log in and not when subsequent commands are issued. The .login file should include instructions for initializing remote terminals and setting up special variables called environment variables. It is best to set the same environment variables in your .login and .cshrc files. See Appendix C for samples on setting terminal characteristics and branching on machine types.

1.3.3 .profile file

In Unix System V, the Bourne shell may be the default shell program. The standard command-line prompt in the Bourne shell is a "$." When you log in to one of these systems, .profile is executed. This file is comparable to the C-shell's .cshrc and .login files and contains information for customizing your environment. The syntax for defining environment variables and aliases differs from that for the C-shell. These differences will not be discussed in this section. For more information on the Bourne shell, see Chapter 2.2 or the Unix System V Release 4 User's Guide.

1.3.4 .logout file

When you log out, the C-shell executes commands in the .logout file. This file is useful for running housekeeping commands. As in the .cshrc and .login files, you can include any commands that you would type on the command line. Do not put interactive commands in this file.

1.3.5 Shell Variables

Shell variables are variables that control your shell environment. There are two types of shell variables, "boolean" and "string." Boolean variables are like switches; they either set or unset a variable. String variables accept characters as variables. Following are some examples of shell variables you might wish to include in your .cshrc file:
 
set history=40
String variable that tells the C-shell to record the last 40 commands typed. A list of these commands can be seen by typing history.
set noclobber
Boolean variable that prevents unintentional overwrite of files when copying, cp, or using the > symbol for redirecting output.
set path=(...)
String variable that sets the path variable to include the standard directories to be searched when executing a command.
set path = (. /usr/ucb /bin /usr/bin /usr/local/bin)
set ignoreeof
Boolean variable that prevents accidental logout when you type CTRL-d.
set prompt=
String variable that sets an alternate command line prompt. The following example would set your prompt to show the machine name.
set prompt= "`hostname`"
umask ugo
String variable that sets default permissions mask for new files. The settings are the complement of the chmod command. For example, a chmod of 755 means a umask of 022.
umask 022 Remove write access by group and other.
umask 066 Remove read and write access by group and other.
For more information on file protections, see Chapter 3. For additional information on shell commands, see Chapter 2.

1.3.6 Shell Aliases

Aliases allow you to assign alternate names to commands or a series of commands. They can be used as a type of shorthand for simplifying commands you execute routinely. The syntax for making an alias is as follows: 
        alias aliasname  'command'
Following are some sample aliases and what they do: 
 alias dir 'ls -l -f'        Typing dir performs 
                             a long listing of your directories.
 alias memos 'cd /users/jones/memos' 
                             Typing memos sets 
                             default to specified directory.
For more details on aliases, see Chapter 2.

1.3.7 Environment Variables

Environmental variables are useful for storing information that programs need to know, such as default terminal and printer information. To set an environment variable, use the setenv command. This command has two required arguments, the name of the variable and its value. 
        setenv name value
Although not required, the convention is to use all capital letters for names of environment variables The commands printenv and env will display your current environment variable settings to your terminal screen. Some basic environment variables needed for our environment are as follows:
setenv TERM term-type
Sets terminal type. This can be either VT100 or xterm depending on your device.
setenv LASER printer
The LASER environment variable is used by utilities such as dotex and gpr.
setenv PRINTER printer
The PRINTER variable is used by the lpr and qpr commands and the elm mail facility on BSD systems.
setenv LPDEST printer
The LPDEST variable is used by the lp and qpr commands and the elm mail facility on SYSV systems.
setenv DISPLAY IP Addr:0
The DISPLAY variable is necessary for X window applications. You can also use the syntax

setenv DISPLAY workstation:0.0.
For example:
setenv DISPLAY 128.117.88.102:0.0
setenv DISPLAY mimosa:0.0
setenv USER username
Defines who you are.
setenv EDITOR vi
Defines your default editor (in this case, vi). This variable is defined by other programs, such as Mail.
To remove an environment variable, use the command, unsetenv. For example, to remove the LASER variable, enter: 
        unsetenv LASER

On-line Information

Hardcopy References


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Last Modified: 1 December 2002