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Document generated on: 2019-01-17 (revision: 6924) Table of Contents Preface .............................................................................................................................................. xi I System Configuration ....................................................................................................................... 1 1 Yum ........................................................................................................................................ 5 1.1 About Yum ................................................................................................................... 5 1.2 About ULN ................................................................................................................... 5 1.3 Yum Configuration ........................................................................................................ 5 1.3.1 Configuring Use of a Proxy Server ..................................................................... 6 1.3.2 Yum Repository Configuration ............................................................................ 7 1.3.3 Downloading the Oracle Linux Yum Server Repository Files ................................. 8 1.3.4 Using Yum Utilities to Manage Configuration ....................................................... 9 1.4 Using Yum from the Command Line ............................................................................. 9 1.5 Yum Groups ............................................................................................................... 11 1.6 Installing and Using the Yum Security Plugin ............................................................... 11 1.7 Switching CentOS or Scientific Linux Systems to Use the Oracle Linux Yum Server ........ 13 1.8 Creating and Using a Local ULN Mirror ....................................................................... 14 1.9 Creating a Local Yum Repository Using an ISO Image ................................................. 14 1.10 Setting up a Local Yum Server Using an ISO Image .................................................. 15 1.11 For More Information About Yum .............................................................................. 16 2 Ksplice .................................................................................................................................. 17 2.1 Overview of Oracle Ksplice ......................................................................................... 17 2.1.1 Supported Kernels ........................................................................................... 17 2.1.2 About Ksplice Updates ..................................................................................... 18 2.1.3 Patching and Updating Your System ................................................................. 18 2.2 About the Ksplice Client Software ............................................................................... 18 2.2.1 About the Ksplice Enhanced Client ................................................................... 18 2.2.2 About the Ksplice Uptrack Client ...................................................................... 19 2.3 Choosing a Ksplice Client ........................................................................................... 20 2.4 Preparing to Use Oracle Ksplice ................................................................................. 20 3 Boot Configuration ................................................................................................................. 21 3.1 About the Boot Process .............................................................................................. 21 3.2 About the GRUB Boot Loader ..................................................................................... 22 3.2.1 About the GRUB Configuration File .................................................................. 23 3.2.2 Configuring a GRUB Password ........................................................................ 26 3.2.3 Using GRUB .................................................................................................... 27 3.3 About Run Levels ....................................................................................................... 27 3.3.1 Displaying the Run Level ................................................................................. 28 3.3.2 Changing the Run Level .................................................................................. 28 3.3.3 Shutting down the System ................................................................................ 28 3.3.4 About Service Scripts ....................................................................................... 28 3.3.5 About the Service Configuration GUI ................................................................ 29 3.3.6 Starting and Stopping Services ......................................................................... 30 3.3.7 Configuring Services to Start at Different Run Levels ......................................... 30 4 System Configuration Settings ............................................................................................... 33 4.1 About /etc/sysconfig Files ............................................................................................ 33 4.2 About the /proc Virtual File System .............................................................................. 34 4.2.1 Virtual Files and Directories Under /proc ........................................................... 35 4.2.2 Changing Kernel Parameters ............................................................................ 38 4.2.3 Parameters that Control System Performance ................................................... 39 4.2.4 Parameters that Control Kernel Panics ............................................................. 40 4.3 About the /sys Virtual File System ..............................................................................