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4.2. Which Log File is Used

In Red Hat Enterprise Linux, the dbus and audit packages are installed by default, unless they are removed from the default package selection. The setroubleshoot-server must be installed using Yum (use the yum install setroubleshoot-server command).
If the auditd daemon is running, an SELinux denial message, such as the following, is written to /var/log/audit/audit.log by default:
type=AVC msg=audit(1223024155.684:49): avc:  denied  { getattr } for  pid=2000 comm="httpd" path="/var/www/html/file1" dev=dm-0 ino=399185 scontext=unconfined_u:system_r:httpd_t:s0 tcontext=system_u:object_r:samba_share_t:s0 tclass=file
In addition, a message similar to the one below is written to the /var/log/message file:
May 7 18:55:56 localhost setroubleshoot: SELinux is preventing httpd (httpd_t) "getattr" to /var/www/html/file1 (samba_share_t). For complete SELinux messages. run sealert -l de7e30d6-5488-466d-a606-92c9f40d316d
In Red Hat Enterprise Linux 7, setroubleshootd no longer constantly runs as a service. However, it is still used to analyze the AVC messages. Two new programs act as a method to start setroubleshoot when needed:
  • The sedispatch utility runs as a part of the audit subsystem. When an AVC denial message is returned, sedispatch sends a message using dbus. These messages go straight to setroubleshootd if it is already running. If it is not running, sedispatch starts it automatically.
  • The seapplet utility runs in the system toolbar, waiting for dbus messages in setroubleshootd. It launches the notification bubble, allowing the user to review AVC messages.

Procedure 4.1. Starting Daemons Automatically

  1. To configure the auditd and rsyslog daemons to automatically start at boot, enter the following commands as the root user:
    ~]# systemctl enable auditd.service
    ~]# systemctl enable rsyslog.service
  2. To ensure that the daemons are enabled, type the following commands at the shell prompt:
    ~]$ systemctl is-enabled auditd
    enabled
    
    ~]$ systemctl is-enabled rsyslog
    enabled
    
    Alternatively, use the systemctl status service-name.service command and search for the keyword enabled in the command output, for example:
    ~]$ systemctl status auditd.service | grep enabled
    auditd.service - Security Auditing Service
       Loaded: loaded (/usr/lib/systemd/system/auditd.service; enabled)
    
To learn more on how the systemd daemon manages system services, see the Managing System Services chapter in the System Administrator's Guide.