Linux Administration:
   A Beginner’s Guide
               Fifth Edition
                    WALE SOYINKA




            ...
Copyright © 2009 by The McGraw-Hill Companies. All rights reserved. Manufactured in the United States of America. Except a...
“With the right knowledge, Linux can be clear and simple to understand. This
 book presents the core fundamentals of Linux...
ABOUT THE AUTHOR
         Wale Soyinka (Canada) is a systems/network engineering consultant with several years
         ex...
For more information about this title, click here




                                            CONTENTS

        Forewo...
vi   Linux Administration: A Beginner’s Guide


                     Methods of Installation. . . . . . . . . .         . ...
Contents   vii


              The /etc/shadow File . . . . . . . . . . . . . . . . . . . . . . . . . .             .   . ...
viii   Linux Administration: A Beginner’s Guide


                            Listing Files: ls . . . . . . . . . . . . . ...
Contents   ix


         The init Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .     ...
x   Linux Administration: A Beginner’s Guide


           ▼ 9 Compiling the Linux Kernel . . . . . . . . . . . . . . . . ....
Contents   xi


         How ARP Works. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .           ...
xii   Linux Administration: A Beginner’s Guide


                      Cookbook Solutions . . . . . . . . . . . . .       ...
Contents   xiii


                                                            Part IV
                                    ...
xiv   Linux Administration: A Beginner’s Guide


                      Obtaining and Installing vsftpd . . . . . . . . . ....
Contents   xv


▼ 20 POP and IMAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .         ...
xvi   Linux Administration: A Beginner’s Guide


                     Enabling NFS in Ubuntu . . . . . . . . . . . . . . ....
Contents   xvii


▼ 24 Samba . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .    ...
xviii   Linux Administration: A Beginner’s Guide


                         Searching, Querying, and Modifying the Directo...
Contents   xix


             User-Mode Linux (UML) . . . . . . . . . . . . . . . . . . . . . . . . . .                   ...
FOREWORD
                I
                  n 1999, editor Jane Brownlow approached me to do a book on Linux.
           ...
ACKNOWLEDGMENTS
                         T
                                he list of people whom I would like to acknowle...
INTRODUCTION
                O
                        n October 5, 1991, Linus Torvalds posted this message to the news-
...
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Mc Graw Hill Osborne   Linux Administration Beginners Guide 5th Edition
Upcoming SlideShare
Loading in...5
×

Mc Graw Hill Osborne Linux Administration Beginners Guide 5th Edition

19,132

Published on

Published in: Technology, Business
0 Comments
3 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
19,132
On Slideshare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
292
Comments
0
Likes
3
Embeds 0
No embeds

No notes for slide

Transcript of "Mc Graw Hill Osborne Linux Administration Beginners Guide 5th Edition"

  1. 1. Linux Administration: A Beginner’s Guide Fifth Edition WALE SOYINKA New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto
  2. 2. Copyright © 2009 by The McGraw-Hill Companies. All rights reserved. Manufactured in the United States of America. Except as per- mitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher. 0-07-154625-1 The material in this eBook also appears in the print version of this title: 0-07-154588-3. All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate train- ing programs. For more information, please contact George Hoare, Special Sales, at george_hoare@mcgraw-hill.com or (212) 904- 4069. TERMS OF USE This is a copyrighted work and The McGraw-Hill Companies, Inc. (“McGraw-Hill”) and its licensors reserve all rights in and to the work. Use of this work is subject to these terms. Except as permitted under the Copyright Act of 1976 and the right to store and retrieve one copy of the work, you may not decompile, disassemble, reverse engineer, reproduce, modify, create derivative works based upon, transmit, distribute, disseminate, sell, publish or sublicense the work or any part of it without McGraw-Hill’s prior consent. You may use the work for your own noncommercial and personal use; any other use of the work is strictly prohibited. Your right to use the work may be terminated if you fail to comply with these terms. THE WORK IS PROVIDED “AS IS.” McGRAW-HILL AND ITS LICENSORS MAKE NO GUARANTEES OR WARRANTIES AS TO THE ACCURACY, ADEQUACY OR COMPLETENESS OF OR RESULTS TO BE OBTAINED FROM USING THE WORK, INCLUDING ANY INFORMATION THAT CAN BE ACCESSED THROUGH THE WORK VIA HYPERLINK OR OTHERWISE, AND EXPRESSLY DISCLAIM ANY WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. McGraw-Hill and its licensors do not warrant or guarantee that the functions contained in the work will meet your requirements or that its operation will be uninterrupted or error free. Neither McGraw-Hill nor its licensors shall be liable to you or anyone else for any inaccuracy, error or omission, regardless of cause, in the work or for any damages resulting therefrom. McGraw-Hill has no responsibility for the content of any information accessed through the work. Under no circumstances shall McGraw-Hill and/or its licensors be liable for any indirect, incidental, spe- cial, punitive, consequential or similar damages that result from the use of or inability to use the work, even if any of them has been advised of the possibility of such damages. This limitation of liability shall apply to any claim or cause whatsoever whether such claim or cause arises in contract, tort or otherwise. DOI: 10.1036/0071545883
  3. 3. “With the right knowledge, Linux can be clear and simple to understand. This book presents the core fundamentals of Linux in a manner that is very logical and easy to follow.” —Greg Kurtzer, CTO, Infiscale, Inc. “Wale continues to do a great job explaining complex information in a straightfor- ward manner. All newcomers should start their Linux library with this book.” —Ron Hudson, Senior Field Support Engineer, Intervoice, Inc. “Wale Soyinka did a stellar job in the fourth edition and he was up for the chal- lenge of making the fifth edition his own. It is with great pleasure I present the fifth edition of Linux Administration: A Beginners Guide by Wale Soyinka. This book barely resembles the 500-odd pages written nine years ago in the first edi- tion, and it is without hesitation that I say his new words are for the better.” —From the Foreword by Steve Shah, original author of Linux Administration: A Beginner’s Guide
  4. 4. ABOUT THE AUTHOR Wale Soyinka (Canada) is a systems/network engineering consultant with several years experience in the field. He has written an extensive library of Linux administration train- ing materials. In addition to being a co-author of the fourth edition of Linux Administration: A Beginner’s Guide, he is the author of a projects lab manual—Microsoft Windows 2000 Man- aging Network Environments, which is part of the Microsoft certification series published by Prentice Hall. Wale participates in several open source discussions and projects. His latest project is at caffe*nix (www.caffenix.com) where he usually hangs out. caffe*nix is possibly the world’s first (or only existing) brick-and-mortar store committed and dedi- cated to prompting and showcasing open source technologies and culture. ABOUT THE CONTRIBUTING AUTHOR Steve Shah (San Jose, California) is the chief technology officer (CTO) and co-founder of Asyncast, where he leads the product strategy and engineering groups. Prior to start- ing Asyncast, Steve was the founder and principal of RisingEdge Consulting where he provided strategic marketing services for a number of Silicon Valley infrastructure com- panies. To earn his chops, Steve grew to be a prominent player in network load balanc- ing, application delivery controllers, and Secure Sockets Layer-virtual private network (SSL-VPN) markets as the director of product management at NetScaler (acquired by Citrix) and Array Networks. Before turning into a marketing droid who is eerily com- fortable at a Unix command prompt, Steve was a senior software engineer and systems administrator at numerous companies. Steve holds a bachelor of science (BS) in com- puter science with a minor in creative writing and a master in science (MS) in computer science from University of California Riverside. ABOUT THE TECHNICAL EDITOR Dr. Ibrahim Haddad is director of technology at Motorola, Inc. and is responsible for defining and developing the requirements for Motorola’s open source initiatives. Prior to Motorola, Dr. Haddad managed the carrier-grade Linux and Mobile Linux Initiatives at the Open Source Development Lab (OSDL), which included promoting the develop- ment and adoption of Linux and open source software in the communications industry. Prior to joining OSDL, Dr. Haddad was a senior researcher at the Research & Innova- tion Department of Ericsson’s Corporate Unit of Research. He is a contributing editor for Linux Journal and Enterprise Open Source magazines. Haddad received his BS and MS degrees in computer science from the Lebanese American University, and his PhD in computer science from Concordia University in Montreal, Canada. In 2000, he was awarded by Concordia University both the J.W. McConnell Memorial Graduate Fel- lowship, and the Concordia University 25th Anniversary Fellowship, in recognition for academic excellence. In 2007, he was the winner of the Big Idea Innovation Award in Recognition of Leadership and Vision at Motorola, Inc. Copyright © 2009 by The McGraw-Hill Companies. Click here for terms of use.
  5. 5. For more information about this title, click here CONTENTS Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xx Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxii Part I Installing Linux as a Server ▼ 1 Technical Summary of Linux Distributions . . . . . . . . . . . . . . . . . . . . . . . . 3 Linux—The Operating System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 What Is Open Source Software and GNU All About? . . . . . . 5 What Is the GNU Public License? . . . . . . . . . . . . . . . . . . . . . 7 The Advantages of Open Source Software . . . . . . . . . . . . . . . . . . . 8 Understanding the Differences Between Windows and Linux . . . 9 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 ▼ 2 Installing Linux in a Server Configuration . . . . . . . . . . . . . . . . . . . . . . . 15 Hardware and Environmental Considerations . . . . . . . . . . . . . . 16 Server Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Uptime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Dual-Booting Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 v
  6. 6. vi Linux Administration: A Beginner’s Guide Methods of Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Installing Fedora . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Project Prerequisites. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Carrying Out the Installation. . . . . . . . . . . . . . . . . . . . . . . . 21 Initial System Configuration . . . . . . . . . . . . . . . . . . . . . . . . 36 Installing Ubuntu Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 ▼ 3 Managing Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 The RPM Package Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 The Debian Package Management System . . . . . . . . . . . . . . . . . . 47 APT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Managing Software Using RPM . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Querying for Information the RPM Way (Getting to Know One Another) . . . . . . . . . . . . . . . . . . . . . 48 Installing with RPM (Moving In Together) . . . . . . . . . . . . . 51 Uninstalling Software with RPM (Ending the Relationship) . . 54 Other Things You Can Do with RPM . . . . . . . . . . . . . . . . . 55 Software Management in Ubuntu . . . . . . . . . . . . . . . . . . . . . . . . 58 Querying for Information . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Installing Software in Ubuntu . . . . . . . . . . . . . . . . . . . . . . . 59 Removing Software in Ubuntu . . . . . . . . . . . . . . . . . . . . . . 59 GUI RPM Package Managers . . . . . . . . . . . . . . . . . . . . . . . 60 Compile and Install GNU Software . . . . . . . . . . . . . . . . . . . . . . . 62 Getting and Unpacking the Package . . . . . . . . . . . . . . . . . . 62 Looking for Documentation (Getting to Know Each Other—Again) . . . . . . . . . . . . . . . . 64 Configuring the Package . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Compiling the Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Installing the Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Testing the Software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Cleanup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Common Problems when Building from Source Code . . . . . . . . 67 Problems with Libraries. . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 When There Is No configure Script . . . . . . . . . . . . . . . . . . . 68 Broken Source Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Part II Single-Host Administration ▼ 4 Managing Users . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 What Exactly Constitutes a User?. . . . . . . . . . . . . . . . . . . . . . . . . 74 Where User Information Is Kept . . . . . . . . . . . . . . . . . . . . . 74 The /etc/passwd File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
  7. 7. Contents vii The /etc/shadow File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 The /etc/group File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 User Management Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 Command-Line User Management . . . . . . . . . . . . . . . . . . . 81 GUI User Managers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 Users and Access Permissions . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 Understanding SetUID and SetGID Programs . . . . . . . . . . 88 Pluggable Authentication Modules (PAM) . . . . . . . . . . . . . . . . . 89 How PAM Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 PAM’s Files and Their Locations . . . . . . . . . . . . . . . . . . . . . 90 Configuring PAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 The “Other” File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 “DOH! I Can’t Log In!” . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Debugging PAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 A Grand Tour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 Creating Users with useradd . . . . . . . . . . . . . . . . . . . . . . . . 96 Creating Groups with groupadd . . . . . . . . . . . . . . . . . . . . . 97 Modifying User Attributes with usermod . . . . . . . . . . . . . . 98 Modifying Group Attributes with groupmod . . . . . . . . . . . 99 Deleting Groups and Users with groupdel and userdel . . . 99 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 ▼ 5 The Command Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 An Introduction to BASH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 Job Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Environment Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 Pipes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 Redirection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 Command-Line Shortcuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 Filename Expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 Environment Variables as Parameters . . . . . . . . . . . . . . . . 108 Multiple Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 Backticks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 Documentation Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 The man Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 The texinfo System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 Files, File Types, File Ownership, and File Permissions . . . . . . . . 112 Normal Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 Directories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 Hard Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Symbolic Links. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Block Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Character Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Named Pipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
  8. 8. viii Linux Administration: A Beginner’s Guide Listing Files: ls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Change Ownership: chown . . . . . . . . . . . . . . . . . . . . . . . . . 115 Change Group: chgrp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 Change Mode: chmod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 File Management and Manipulation . . . . . . . . . . . . . . . . . . . . . . 119 Copy Files: cp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 Move Files: mv. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 Link Files: ln. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 Find a File: find . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 File Compression: gzip . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 bzip2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 Create a Directory: mkdir . . . . . . . . . . . . . . . . . . . . . . . . . 122 Remove a Directory: rmdir . . . . . . . . . . . . . . . . . . . . . . . . 123 Show Present Working Directory: pwd . . . . . . . . . . . . . . . 123 Tape Archive: tar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Concatenate Files: cat. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 Display a File One Screen at a Time: more. . . . . . . . . . . . . 126 Disk Utilization: du . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 Show the Directory Location of a File: which . . . . . . . . . . 127 Locate a Command: whereis . . . . . . . . . . . . . . . . . . . . . . . 127 Disk Free: df . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Synchronize Disks: sync . . . . . . . . . . . . . . . . . . . . . . . . . . 128 Moving a User and Its Home Directory . . . . . . . . . . . . . . . . . . . 128 List Processes: ps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 Show an Interactive List of Processes: top . . . . . . . . . . . . . 133 Send a Signal to a Process: kill . . . . . . . . . . . . . . . . . . . . . . 134 Miscellaneous Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Show System Name: uname . . . . . . . . . . . . . . . . . . . . . . . 135 Who Is Logged In: who . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 A Variation on who: w . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 Switch User: su . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 Editors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 vi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 emacs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 joe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 pico . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 ▼ 6 Booting and Shutting Down. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 Boot Loaders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 GRUB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 LILO. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 Bootstrapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
  9. 9. Contents ix The init Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 rc Scripts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 Writing Your Own rc Script . . . . . . . . . . . . . . . . . . . . . . . . 155 Enabling and Disabling Services . . . . . . . . . . . . . . . . . . . . . . . . 159 Disabling a Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 Odds and Ends of Booting and Shutting Down . . . . . . . . . . . . . 162 fsck! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 Booting into Single-User (“Recovery”) Mode . . . . . . . . . . 163 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164 ▼ 7 File Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 The Makeup of File Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 i-Nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 Superblocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 ext3 and ReiserFS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168 Which File System to Use? . . . . . . . . . . . . . . . . . . . . . . . . 169 Managing File Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 Mounting and Unmounting Local Disks . . . . . . . . . . . . . . 169 Using fsck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 Adding a New Disk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 Overview of Partitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 Traditional Disk- and Partition-Naming Conventions . . . 178 Volume Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179 Creating Partitions and Logical Volumes . . . . . . . . . . . . . 180 Creating File Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 ▼ 8 Core System Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 The init Daemon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 upstart: Die init. Die Now!. . . . . . . . . . . . . . . . . . . . . . . . . 195 The /etc/inittab File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196 xinetd and inetd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 The /etc/xinetd.conf File . . . . . . . . . . . . . . . . . . . . . . . . . 200 Examples: A Simple Service Entry and Enabling/Disabling a Service . . . . . . . . . . . . . . . . . . . . . . 205 The Logging Daemon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 Invoking rsyslogd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 Configuring the Logging Daemon . . . . . . . . . . . . . . . . . . . . . . . 208 Log Message Classifications . . . . . . . . . . . . . . . . . . . . . . . 210 Format of /etc/rsyslog.conf . . . . . . . . . . . . . . . . . . . . . . . . 211 The cron Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 The crontab File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 Editing the crontab File . . . . . . . . . . . . . . . . . . . . . . . . . . . 218 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
  10. 10. x Linux Administration: A Beginner’s Guide ▼ 9 Compiling the Linux Kernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221 What Exactly Is a Kernel? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222 Finding the Kernel Source Code. . . . . . . . . . . . . . . . . . . . . . . . . 224 Getting the Correct Kernel Version . . . . . . . . . . . . . . . . . . 224 Unpacking the Kernel Source Code . . . . . . . . . . . . . . . . . . 225 Building the Kernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 Preparing to Configure the Kernel . . . . . . . . . . . . . . . . . . 227 Kernel Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 Compiling the Kernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 Installing the Kernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233 Booting the Kernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235 The Author Lied—It Didn’t Work! . . . . . . . . . . . . . . . . . . 235 Patching the Kernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 Downloading and Applying Patches. . . . . . . . . . . . . . . . . 237 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 ▼ 10 Knobs and Dials: proc and SysFS File Systems . . . . . . . . . . . . . . . . . . 241 What’s Inside the /proc Directory? . . . . . . . . . . . . . . . . . . . . . . 242 Tweaking Files Inside of /proc . . . . . . . . . . . . . . . . . . . . . 243 Some Useful /proc Entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244 Enumerated /proc Entries . . . . . . . . . . . . . . . . . . . . . . . . . 246 Common proc Settings and Reports . . . . . . . . . . . . . . . . . . . . . . 247 SYN Flood Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248 Issues on High-Volume Servers . . . . . . . . . . . . . . . . . . . . . 249 Debugging Hardware Conflicts . . . . . . . . . . . . . . . . . . . . . 249 SysFS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252 Part III Security and Networking ▼ 11 TCP/IP for System Administrators . . . . . . . . . . . . . . . . . . . . . . . . . . . 255 The Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256 TCP/IP Model and the OSI Model . . . . . . . . . . . . . . . . . . 259 Headers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 IP (IPv4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 TCP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268 UDP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272 A Complete TCP Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 Opening a Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 Transferring Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 Closing the Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
  11. 11. Contents xi How ARP Works. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276 The ARP Header: ARP Works with Other Protocols, Too! . . . 277 Bringing IP Networks Together . . . . . . . . . . . . . . . . . . . . . . . . . 278 Hosts and Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Subnetting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279 Netmasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280 Static Routing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282 Dynamic Routing with RIP . . . . . . . . . . . . . . . . . . . . . . . . 284 Digging into tcpdump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289 A Few General Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289 Graphing Odds and Ends . . . . . . . . . . . . . . . . . . . . . . . . . 293 IPv6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294 IPv6 Address Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294 IPv6 Address Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 IPv6 Backward Compatibility . . . . . . . . . . . . . . . . . . . . . . 295 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296 ▼ 12 Network Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299 Modules and Network Interfaces . . . . . . . . . . . . . . . . . . . . . . . . 300 Network Device Configuration Utilities (ip and ifconfig) . . . 301 IP Aliasing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 Setting Up NICs at Boot Time . . . . . . . . . . . . . . . . . . . . . . 304 Managing Routes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 Simple Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309 Displaying Routes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311 A Simple Linux Router . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314 Routing with Static Routes . . . . . . . . . . . . . . . . . . . . . . . . 314 How Linux Chooses an IP Address . . . . . . . . . . . . . . . . . . . . . . 317 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317 ▼ 13 The Linux Firewall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319 How Netfilter Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320 A NAT Primer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321 NAT-Friendly Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . 324 Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325 Installing Netfilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328 Enabling Netfilter in the Kernel. . . . . . . . . . . . . . . . . . . . . 328 Required Kernel Options . . . . . . . . . . . . . . . . . . . . . . . . . . 329 Optional but Sensible Kernel Options . . . . . . . . . . . . . . . . 329 Other Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330 Configuring Netfilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331 Saving Your Netfilter Configuration . . . . . . . . . . . . . . . . . 331 The iptables Command . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
  12. 12. xii Linux Administration: A Beginner’s Guide Cookbook Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340 Rusty’s Three-Line NAT . . . . . . . . . . . . . . . . . . . . . . . . . . 341 Configuring a Simple Firewall. . . . . . . . . . . . . . . . . . . . . . 342 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 344 ▼ 14 Local Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345 Common Sources of Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347 SetUID Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347 Unnecessary Processes. . . . . . . . . . . . . . . . . . . . . . . . . . . . 349 Picking the Right Runlevel to Boot Into . . . . . . . . . . . . . . . . . . . 350 Non-human Accounts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351 Limited Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352 Mitigating Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354 Using Chroot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354 SELinux . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 357 AppArmor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358 Monitoring Your System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358 Logging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358 Using ps and netstat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359 Using df . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359 Automated Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . 359 Mailing Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360 ▼ 15 Network Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361 TCP/IP and Network Security . . . . . . . . . . . . . . . . . . . . . . . . . . 362 The Importance of Port Numbers . . . . . . . . . . . . . . . . . . . 362 Tracking Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363 Using the netstat Command . . . . . . . . . . . . . . . . . . . . . . . 363 Security Implications of netstat’s Output . . . . . . . . . . . . . 364 Binding to an Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365 Shutting Down Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366 Shutting Down xinetd and inetd Services . . . . . . . . . . . . . 366 Monitoring Your System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368 Making the Best Use of syslog . . . . . . . . . . . . . . . . . . . . . . 368 Monitoring Bandwidth with MRTG . . . . . . . . . . . . . . . . . 370 Handling Attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370 Trust Nothing (and No One) . . . . . . . . . . . . . . . . . . . . . . . 370 Change Your Passwords . . . . . . . . . . . . . . . . . . . . . . . . . . 371 Pull the Plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371 Network Security Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371 nmap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371 Wireshark/tcpdump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373
  13. 13. Contents xiii Part IV Internet Services ▼ 16 DNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377 The Hosts File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378 Understanding How DNS Works . . . . . . . . . . . . . . . . . . . . . . . . 379 Domain and Host Naming Conventions . . . . . . . . . . . . . . 379 Subdomains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382 The in-addr.arpa Domain . . . . . . . . . . . . . . . . . . . . . . . . . 383 Types of Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383 Installing a DNS Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 Understanding the BIND Configuration File . . . . . . . . . . 387 The Specifics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 388 Configuring a DNS Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391 Defining a Primary Zone in the named.conf File . . . . . . . 391 Defining a Secondary Zone in the named.conf File . . . . . . 392 Defining a Caching Zone in the named.conf File . . . . . . . 393 DNS Records Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394 SOA: Start of Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . 394 NS: Name Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395 A: Address Record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396 PTR: Pointer Record. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396 MX: Mail Exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397 CNAME: Canonical Name . . . . . . . . . . . . . . . . . . . . . . . . 397 RP and TXT: The Documentation Entries . . . . . . . . . . . . . 398 Setting Up BIND Database Files . . . . . . . . . . . . . . . . . . . . . . . . . 398 Breaking Out the Individual Steps . . . . . . . . . . . . . . . . . . 400 The DNS Toolbox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404 host . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404 dig . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 406 nslookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407 whois . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408 nsupdate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408 The rndc Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 409 Configuring DNS Clients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410 The Resolver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410 Configuring the Client . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413 ▼ 17 FTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415 The Mechanics of FTP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 416 Client/Server Interactions . . . . . . . . . . . . . . . . . . . . . . . . . 416
  14. 14. xiv Linux Administration: A Beginner’s Guide Obtaining and Installing vsftpd . . . . . . . . . . . . . . . . . . . . . . . . . 418 Configuring vsftpd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418 Starting and Testing the FTP Server. . . . . . . . . . . . . . . . . . 423 Customizing the FTP Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . 426 Setting Up an Anonymous-Only FTP Server . . . . . . . . . . . 426 Setting Up an FTP Server with Virtual Users . . . . . . . . . . 427 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 431 ▼ 18 Apache Web Server. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 433 Understanding the HTTP Protocol . . . . . . . . . . . . . . . . . . . . . . . 434 Headers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 434 Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435 Process Ownership and Security . . . . . . . . . . . . . . . . . . . . 436 Installing the Apache HTTP Server . . . . . . . . . . . . . . . . . . . . . . 437 Apache Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 438 Starting Up and Shutting Down Apache . . . . . . . . . . . . . . . . . . 439 Starting Apache at Boot Time . . . . . . . . . . . . . . . . . . . . . . 440 Testing Your Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441 Configuring Apache . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441 Creating a Simple Root-Level Page . . . . . . . . . . . . . . . . . . 442 Apache Configuration Files . . . . . . . . . . . . . . . . . . . . . . . . 442 Common Configuration Options . . . . . . . . . . . . . . . . . . . . 442 Troubleshooting Apache. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 448 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449 ▼ 19 SMTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451 Understanding SMTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452 Rudimentary SMTP Details . . . . . . . . . . . . . . . . . . . . . . . . 452 Security Implications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454 Installing the Postfix Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 Installing Postfix via RPM in Fedora . . . . . . . . . . . . . . . . . 455 Installing Postfix via APT in Ubuntu . . . . . . . . . . . . . . . . . 456 Configuring the Postfix Server . . . . . . . . . . . . . . . . . . . . . . . . . . 458 The main.cf File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 459 Checking Your Configuration . . . . . . . . . . . . . . . . . . . . . . 461 Running the Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 462 Checking the Mail Queue . . . . . . . . . . . . . . . . . . . . . . . . . 462 Flushing the Mail Queue . . . . . . . . . . . . . . . . . . . . . . . . . . 462 The newaliases Command . . . . . . . . . . . . . . . . . . . . . . . . . 462 Making Sure Everything Works. . . . . . . . . . . . . . . . . . . . . 462 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463
  15. 15. Contents xv ▼ 20 POP and IMAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465 POP and IMAP Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 468 Installing the UW-IMAP and POP3 Server. . . . . . . . . . . . . . . . . 468 Installing UW-IMAP from Source . . . . . . . . . . . . . . . . . . . 469 Running UW-IMAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471 Other Issues with Mail Services . . . . . . . . . . . . . . . . . . . . . . . . . 474 SSL Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474 Testing IMAP Connectivity with SSL . . . . . . . . . . . . . . . . 475 Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475 Log Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476 ▼ 21 The Secure Shell (SSH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 479 Understanding Public Key Cryptography . . . . . . . . . . . . . . . . . 480 Key Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482 Cryptography References . . . . . . . . . . . . . . . . . . . . . . . . . 483 Understanding SSH Versions and Distributions . . . . . . . . . . . . 484 OpenSSH and OpenBSD . . . . . . . . . . . . . . . . . . . . . . . . . . 484 Alternative Vendors for SSH Clients . . . . . . . . . . . . . . . . . 484 Installing OpenSSH via RPM in Fedora . . . . . . . . . . . . . . 486 Installing OpenSSH via APT in Ubuntu . . . . . . . . . . . . . . 486 Downloading, Compiling, and Installing OpenSSH from Source 486 Server Startup and Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . 489 SSHD Configuration File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 490 Using OpenSSH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 490 Secure Shell (SSH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 Creating a Secure Tunnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 OpenSSH Shell Tricks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 494 Secure Copy (SCP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 495 Secure FTP (SFTP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 495 Files Used by the OpenSSH Client . . . . . . . . . . . . . . . . . . 496 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 496 Part V Intranet Services ▼ 22 Network File System (NFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501 The Mechanics of NFS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 502 Versions of NFS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503 Security Considerations for NFS . . . . . . . . . . . . . . . . . . . . 504 Mount and Access a Partition . . . . . . . . . . . . . . . . . . . . . . 504 Enabling NFS in Fedora . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 505
  16. 16. xvi Linux Administration: A Beginner’s Guide Enabling NFS in Ubuntu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 506 The Components of NFS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 507 Kernel Support for NFS . . . . . . . . . . . . . . . . . . . . . . . . . . . 508 Configuring an NFS Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . 508 The /etc/exports Configuration File . . . . . . . . . . . . . . . . . 508 Configuring NFS Clients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512 The mount Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513 Soft vs. Hard Mounts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 515 Cross-Mounting Disks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 515 The Importance of the intr Option . . . . . . . . . . . . . . . . . . . 516 Performance Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 516 Troubleshooting Client-Side NFS Issues . . . . . . . . . . . . . . . . . . 517 Stale File Handles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 517 Permission Denied . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 517 Sample NFS Client and NFS Server Configuration . . . . . . . . . . 518 Common Uses for NFS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 520 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 520 ▼ 23 Network Information Service (NIS) . . . . . . . . . . . . . . . . . . . . . . . . . . . 523 Inside NIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524 The NIS Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525 Domains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 526 Configuring the Master NIS Server . . . . . . . . . . . . . . . . . . . . . . 526 Establishing the Domain Name . . . . . . . . . . . . . . . . . . . . . 527 Starting NIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 528 Editing the Makefile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 528 Using ypinit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 532 Configuring an NIS Client . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 534 Editing the /etc/yp.conf File . . . . . . . . . . . . . . . . . . . . . . . 534 Enabling and Starting ypbind . . . . . . . . . . . . . . . . . . . . . . 535 Editing the /etc/nsswitch.conf File . . . . . . . . . . . . . . . . . . . . . . 536 NIS at Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 538 Testing Your NIS Client Configuration . . . . . . . . . . . . . . . 540 Configuring a Secondary NIS Server . . . . . . . . . . . . . . . . . . . . . 540 Setting the Domain Name . . . . . . . . . . . . . . . . . . . . . . . . . 540 Setting Up the NIS Master to Push to Slaves . . . . . . . . . . . 541 Running ypinit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 541 NIS Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 542 Using NIS in Configuration Files. . . . . . . . . . . . . . . . . . . . 543 Implementing NIS in a Real Network . . . . . . . . . . . . . . . . . . . . 543 A Small Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 544 A Segmented Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . 544 Networks Bigger Than Buildings . . . . . . . . . . . . . . . . . . . 545 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 545
  17. 17. Contents xvii ▼ 24 Samba . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 547 The Mechanics of SMB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 548 Usernames and Passwords . . . . . . . . . . . . . . . . . . . . . . . . 548 Encrypted Passwords . . . . . . . . . . . . . . . . . . . . . . . . . . . . 549 Samba Daemons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 549 Installing Samba via RPM . . . . . . . . . . . . . . . . . . . . . . . . . 550 Installing Samba via APT. . . . . . . . . . . . . . . . . . . . . . . . . . 551 Samba Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 552 Starting and Stopping Samba . . . . . . . . . . . . . . . . . . . . . . 553 Using SWAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 554 Setting Up SWAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 554 The SWAT Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 556 Globals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557 Shares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557 Printers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557 Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557 View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 558 Password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 558 Creating a Share . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 558 Using smbclient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 560 Mounting Remote Samba Shares . . . . . . . . . . . . . . . . . . . . . . . . 563 Creating Samba Users . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 563 Allowing Null Passwords . . . . . . . . . . . . . . . . . . . . . . . . . 564 Changing Passwords with smbpasswd . . . . . . . . . . . . . . . 564 Using Samba to Authenticate Against a Windows Server . . . . . 565 Troubleshooting SAMBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567 ▼ 25 LDAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 569 LDAP Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 570 LDAP Directory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 570 Client/Server Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571 Uses of LDAP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572 LDAP Terminologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572 OpenLDAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 573 Server-Side Daemons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 573 OpenLDAP Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 574 Installing OpenLDAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 574 Configuring OpenLDAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 576 Configuring slapd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577 Starting and Stopping slapd . . . . . . . . . . . . . . . . . . . . . . . 580 Configuring OpenLDAP Clients . . . . . . . . . . . . . . . . . . . . . . . . 581 Creating Directory Entries . . . . . . . . . . . . . . . . . . . . . . . . . 581
  18. 18. xviii Linux Administration: A Beginner’s Guide Searching, Querying, and Modifying the Directory . . . . . . . . . . 583 Using OpenLDAP for User Authentication . . . . . . . . . . . . . . . . 584 Configuring the Server . . . . . . . . . . . . . . . . . . . . . . . . . . . 584 Configuring the Client . . . . . . . . . . . . . . . . . . . . . . . . . . . . 586 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 587 ▼ 26 Printing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 589 Printing Terminologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 590 The CUPS System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 591 Running CUPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 591 Installing CUPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 591 Configuring CUPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 593 Adding Printers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 594 Local Printers and Remote Printers . . . . . . . . . . . . . . . . . . 595 Routine CUPS Administration . . . . . . . . . . . . . . . . . . . . . . . . . . 600 Setting the Default Printer . . . . . . . . . . . . . . . . . . . . . . . . . 600 Enabling and Disabling Printers . . . . . . . . . . . . . . . . . . . . 600 Accepting and Rejecting Print Jobs . . . . . . . . . . . . . . . . . . 600 Managing Printing Privileges . . . . . . . . . . . . . . . . . . . . . . 601 Deleting Printers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601 Managing Printers via the Web Interface . . . . . . . . . . . . . . . . . . 602 Using Client-Side Printing Tools . . . . . . . . . . . . . . . . . . . . . . . . 603 lpr. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 603 lpq . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 604 lprm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 604 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 605 ▼ 27 DHCP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 607 The Mechanics of DHCP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 608 The DHCP Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 609 Installing DHCP Software via RPM. . . . . . . . . . . . . . . . . . 609 Installing DHCP Software via APT in Ubuntu . . . . . . . . . 609 Configuring the DHCP Server . . . . . . . . . . . . . . . . . . . . . . 610 A Sample dhcpd.conf File . . . . . . . . . . . . . . . . . . . . . . . . . 616 The DHCP Client Daemon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 617 Configuring the DHCP Client . . . . . . . . . . . . . . . . . . . . . . 617 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 619 ▼ 28 Virtualization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 621 Why Virtualize? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 622 Virtualization Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . 622 Virtualization Implementations . . . . . . . . . . . . . . . . . . . . . . . . . 623 QEMU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 624 Xen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 624
  19. 19. Contents xix User-Mode Linux (UML) . . . . . . . . . . . . . . . . . . . . . . . . . . 624 Kernel-based Virtual Machines (KVM) . . . . . . . . . . . . . . . 624 VMware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 624 Virtualbox . .