12.2. Configuring the Services To allow you to configure which services are started at boot time, Red Hat Enterprise Linux is shipped with the following utilities: the Service Configuration graphical application, the ntsysv text user interface, and the chkconfig command-line tool. Important To ensure optimal performance on POWER architecture, it is recommended that the irqbalance service is enabled. In most cases, this service is installed and configured to run during the Red Hat Enterprise Linux 6 installation. To verify that irqbalance is running, as root , type the following at a shell prompt: For information on how to enable and run a service using a graphical user interface, see Section 12.2.1, "Using the Service Configuration Utility" . For instructions on how to perform these task on the command line, see Section 12.2.3, "Using the chkconfig Utility" and Section 12.3, "Running Services" respectively. 12.2.1. Using the Service Configuration Utility The Service Configuration utility is a graphical application developed by Red Hat to configure which services are started in a particular runlevel, as well as to start, stop, and restart them from the menu. To start the utility, select System Administration Services from the panel, or type the command system-config-services at a shell prompt. Note The system-config-services utility is provided by the system-config-services package, which may not be installed by default on your version of Red Hat Enterprise Linux. To ensure that, first run the following command: If the package is not installed by default, install it manually by running the following command as root: Figure 12.1. The Service Configuration utility The utility displays the list of all available services (services from the /etc/rc.d/init.d/ directory, as well as services controlled by xinetd ) along with their description and the current status. For a complete list of used icons and an explanation of their meaning, see Table 12.2, "Possible service states" . Note that unless you are already authenticated, you will be prompted to enter the superuser password the first time you make a change. Table 12.2. Possible service states Icon Description The service is enabled. The service is disabled. The service is enabled for selected runlevels only. The service is running. The service is stopped. There is something wrong with the service. The status of the service is unknown. 12.2.1.1. Enabling and Disabling a Service To enable a service, select it from the list and either click the Enable button on the toolbar, or choose Service Enable from the main menu. To disable a service, select it from the list and either click the Disable button on the toolbar, or choose Service Disable from the main menu. 12.2.1.2. Starting, Restarting, and Stopping a Service To start a service, select it from the list and either click the Start button on the toolbar, or choose Service Start from the main menu. Note that this option is not available for services controlled by xinetd , as they are started by it on demand. To restart a running service, select it from the list and either click the Restart button on the toolbar, or choose Service Restart from the main menu. Note that this option is not available for services controlled by xinetd , as they are started and stopped by it automatically. To stop a service, select it from the list and either click the Stop button on the toolbar, or choose Service Stop from the main menu. Note that this option is not available for services controlled by xinetd , as they are stopped by it when their job is finished. 12.2.1.3. Selecting Runlevels To enable the service for certain runlevels only, select it from the list and either click the Customize button on the toolbar, or choose Service Customize from the main menu. Then select the check box beside each runlevel in which you want the service to run. Note that this option is not available for services controlled by xinetd .

Commands:
~]# service irqbalance status irqbalance (pid 1234) is running
~]USD rpm -q system-config-services
~]# yum install system-config-services