Accessing Your System 2

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Accessing Your System 2

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Accessing Your System 2 Objectives Upon completion of this module, you should be able to : • List the characteristics of an effective password • Change your password • Describe the function of a mouse button • Log in and log out of a system from the command line • Log in and out of a CDE session • Manipulate windows within the CDE • Invoke and use menus and menu bars Discussion – Passwords are a major key to a secure system. What characteristics would a good password have? User Accounts You must have a user account on the system to log in. The user account is defined in the /etc/passwd file and contains the elements which identify each unique user to the system. System administrators are responsible for creating and maintaining user accounts. The Root Account The root account is the system administration account and is set up by the installation process. The root login account owns all system files and has access to all files. The /etc/passwd Entry Each entry in the /etc/passwd file is made up of seven fields separated by a colon. • Login ID – Is the identification required by the operating system for a successful login. It is the user’s “public name.” Depending on the system administrator, login IDs are usually some combination of a user’s first and last names. For example, user Bob Wood’s login ID might be bobw, bwood, woodb, or bw2. The login ID must:  Be limited to 32 characters  Do not accept special characters: !, @, #, $, %,^, &  Be unique • Placeholder – Maintains the field for the password, which is kept in the /etc/shadow file. The /etc/shadow file contains encrypted passwords and password aging information (for example, how long before a user must change a password and how long a password must be in use before it can be changed). This file can only be read by the system administrator. • UID – Identifies the user to the operating system. • GID – Identifies the primary group to which the user belongs. • Comment – Is usually the full name of the user. • Login directory – Is commonly referred to as the “home” directory, where users store their files. • Default shell – Defines which shell the user will have upon login. Password Requirements Your password protects your account from unauthorized access. In the Linux computing environment, a password • Should contain at least two alphabetic characters and one numeric or special character • Should differ from the login ID • Should differ from the previous password by at least three characters • May contain spaces • These password requirements do not apply to the system administrator (superuser). The Mouse Buttons The mouse settings can be modified to suit a user’s preferences. Once a setting has been modified, that setting can be stored into a userspecific file. This means that any personalized settings will be the default whenever a CDE session is initiated. The Left Mouse Button Most actions use the left mouse button, alternatively known as button 1 or the SELECT button. This button is used to make selections in any of the following ways: • Make a window active by clicking the left mouse button while the mouse pointer is in that window area • Invoke a window menu by clicking on the left mouse button while the mouse pointer is on the window’s menu box area • Select an option from the Front Panel • Select a File or Folder icon while working with the File Manager • Open an icon by double-clicking the left mouse button while the pointer is over the icon • Highlight text to be selected by dragging over the text area, while the left mouse button is being pressed The Middle Mouse Button Button 2, also known as the ADJUST button, is used to paste selected text. The text must have been selected using the left mouse button as described previously. The Right Mouse Button When the right mouse button, or MENU button, is clicked or held down, a menu of choices will appear. The options available on the menu will be determined by the position of the mouse pointer when button 3 was pressed. Note – For the purposes of this course, you will be instructed to left or right click to perform a specific action. This assumes the standard right-hand configuration of the buttons. These notes will instruct you when a double-click is required. Logging In Logging in identifies you to the system. You can log in using the login screen shown in CDE (graphic mode) , or at the command line (text mode). Logging in text mode To log in at the command line, follow these steps: 1. Type your user name (login ID) at the prompt and press Return. 2. Type your password at the password prompt and press Return. Note – Your password does not appear as you type it. By default, if you do not have a password, you are automatically prompted for one during the initial login. Logging in graphic mode The CDE login screen replaces the usual login prompt. You must enter your login name into the appropriate boxed area, then press the Return key or left click on the OK button. If you log in incorrectly, you must repeat the procedure of entering your login name and password. Note – If you make a mistake when entering either your login name or your password, you will be required to reenter both pieces of information. Changing Your Password Changing your password frequently helps prevent unauthorized access to your system. To change your password: 1. If you are in text mode, goto next step. If you are logged into a CDE session, right click on the background to bring up the Workspace Manager, click on Programs, and open a terminal window. (On some systems, the Workspace Manager will have a menu selection labelled Windows. If that is the case, click on this instead of Programs to access a terminal window.). 2. Type the passwd command after the system prompt and press Return. 3. When the prompt Enter login password: appears, type your current password and press Return. 4. When the prompt New password appears, type your new password and press Return. 5. When prompted, retype the new password and press Return. (This is required for verification of the new password by the system.) Example $ passwd passwd: Changing password for user2 Enter login password: New password: Re-enter new passwd: $  If the users are unable to change their passwords due to cred table errors, use the following command on the Network Information Service Plus (NIS+) server: newkey -u username -s nisplus This puts the user login password in the NIS+ cred table. Exercise: Accessing Your System Exercise objective – In this exercise, you will practice logging in on the command line, changing your password, logging out, and other basic CDE skills. Tasks Complete the following steps: 1. Obtain a user name and password from your instructor. 2. Log in to the system . 3. Change the password to mypass1. 4. Log out of the system. 5. Log back in to the system with the new password, then log back out. 6. At the CDE login screen, enter the following (incorrect) details: Login Name: nosuchuser Password: wrong Observe the information displayed on the screen. 7. At the CDE login screen, enter your own (correct) details and log in to a CDE session. 8. Using the correct mouse and Front Panel buttons, switch from the default workspace display to Workspace Three. From Workspace Three, switch back to Workspace One. 9. Click on the Text Note icon on the Front Panel to open a Text Note window. 10. Once the Text Note window has been opened, convert the window to an icon. 11. Convert the Text Note icon back to a Text Note window. 12. Move the Text Note window to another position on your workspace display. 13. Make the Text Note window take up all of your workspace display area. 14. Reduce the Text Note window back to its previous size. 15. Type some text into the Text Note window, then attempt to close the window. 16. Confirm that you want to close the window without saving the text. 17. Exit from your current CDE session. 18. Confirm that you want to log out. 19. Once you are back at the CDE Login Screen, log in again using your allocated login name and password. Workshop Labs Use what you have learned so far in this course to work through the following: 1. A new employee is given a Sun workstation to log in to. After repeated attempts, the login fails. Why might this have happened? 2. A user would like to be able to do some command-line aliasing to make issuing commands easier. What would the system administrator have to have done to make this work every time the user logs in? Exercise Summary Discussion – Take a few minutes to discuss what experiences, issues, or discoveries you had during the lab exercises.  Manage the discussion here based on the time allowed for this module, which was given in the “About This Course” module. If you find you do not have time to spend on discussion, then just highlight the key concepts students should have learned from the lab exercise. • Experiences  Ask students what their overall experiences with this exercise have been. You might want to go over any trouble spots or especially confusing areas at this time. • Interpretations  Ask students to interpret what they observed during any aspects of this exercise. • Conclusions  Have students articulate any conclusions they reached as a result of this exercise experience. • ✡pplications  Explore with students how they might apply what they learned in this exercise to situations at their workplace. Exercise Solutions 3. Change the password to mypass1. $ passwd old password: new password: re-enter new password: 4. Log out of the system. $exit Check Your Progress Before continuing on to the next module, check that you are able to accomplish or answer the following:  List the characteristics of an effective password  Change your password  Describe the function of a mouse button  Log in and log out of a system from the command line  Log in and out of a CDE session  Manipulate windows within the CDE  Invoke and use menus and menu bars Think Beyond On a UNIX system, it is not unusual for users to be forced to change their passwords on a regular basis. What are some reasons for this? . information. Changing Your Password Changing your password frequently helps prevent unauthorized access to your system. To change your password: 1. If you. password from your instructor. 2. Log in to the system . 3. Change the password to mypass1. 4. Log out of the system. 5. Log back in to the system with the

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