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Chapter 25. Viewing and Managing Log Files

Log files are files that contain letters nearly the system, including the kernel, services, and applications running on it. There are different log files for unlike information. For example, in that location is a default system log file, a log file just for security letters, and a log file for cron tasks.

Log files tin be very useful when trying to troubleshoot a trouble with the system such as trying to load a kernel driver or when looking for unauthorized login attempts to the system. This chapter discusses where to find log files, how to view log files, and what to look for in log files.

Some log files are controlled past a daemon called rsyslogd. The rsyslogd daemon is an enhanced replacement for previous sysklogd , and provides extended filtering, encryption protected relaying of messages, various configuration options, input and output modules, back up for transportation via the TCP or UDP protocols. Notation that rsyslog is compatible with sysklogd .

25.i. Installing rsyslog

Version 5 of rsyslog , provided in the rsyslog package, is installed by default in Red Chapeau Enterprise Linux 6. If required, to ensure that information technology is, result the following command as root: 

~]#                          yum install rsyslog                          Loaded plugins: product-id, refresh-packagekit, subscription-director Package rsyslog-5.viii.10-10.el6_6.i686 already installed and latest version Nothing to do

25.1.1. Upgrading to rsyslog version 7

Version vii of rsyslog , provided in the rsyslog7 package, is bachelor in Blood-red Hat Enterprise Linux 6. Information technology provides a number of enhancements over version 5, in particular college processing performance and support for more than plug-ins. If required, to modify to version vii, brand use of the yum shell utility as described below.

Procedure 25.one. Upgrading to rsyslog vii

To upgrade from rsyslog version five to rsyslog version 7, it is necessary to install and remove the relevant packages simultaneously. This can exist accomplished using the yum shell utility.

  1. Enter the following command as root to start the yum beat: 

    ~]#                                  yum shell                                  Loaded plugins: production-id, refresh-packagekit, subscription-manager >

    The yum crush prompt appears.

  2. Enter the following commands to install the rsyslog7 package and remove the rsyslog packet. 

    >                                                                      install rsyslog7                                                                    >                                                                      remove rsyslog

  3. Enter run to offset the process: 

    >                                                                      run                                                                    --> Running transaction check ---> Bundle rsyslog.i686 0:5.8.ten-x.el6_6 will be erased ---> Parcel rsyslog7.i686 0:7.4.10-3.el6_6 will be installed --> Finished Dependency Resolution  ============================================================================  Package        Arch     Version           Repository                  Size ============================================================================ Installing:                                                            rsyslog7       i686     7.four.x-3.el6_6    rhel-six-workstation-rpms    1.3 M Removing:                                                              rsyslog        i686     v.eight.10-10.el6_6   @rhel-vi-workstation-rpms   2.1 Chiliad                                                                       Transaction Summary                                                  ============================================================================ Install  ane Packet Remove   one Package  Total download size: i.3 M Is this ok [y/d/N]:                                    y

  4. Enter y when prompted to beginning the upgrade.

  5. When the upgrade is completed, the yum beat out prompt is displayed. Enter quit or exit to get out the shell: 

    Finished Transaction >                                  quit                                  Leaving Shell ~]#