Chapter 5. Network Configuration
NetworkManager is a dynamic network control and configuration system that attempts to keep network devices and connections up and active when they are available. NetworkManager consists of a core daemon, a GNOME Notification Area applet that provides network status information, and graphical configuration tools that can create, edit and remove connections and interfaces. NetworkManager can be used to configure the following types of connections: Ethernet, wireless, mobile broadband (such as cellular 3G), and DSL and PPPoE (Point-to-Point over Ethernet). In addition, NetworkManager allows for the configuration of network aliases, static routes, DNS information and VPN connections, as well as many connection-specific parameters. Finally, NetworkManager provides a rich API via D-Bus which allows applications to query and control network configuration and state.
Previous versions of Red Hat Enterprise Linux shipped with the
Network Administration Tool, which was commonly known as
system-config-network after its command line invocation. In Red Hat Enterprise Linux 6,
NetworkManager replaces the former
Network Administration Tool while providing enhanced functionality, such as user-specific and mobile broadband configuration. It is also possible to configure the network in Red Hat Enterprise Linux 6 by editing interface configuration files; refer to
Chapter 4, Network Interfaces for more information.
NetworkManager may be installed by default on Red Hat Enterprise Linux. To ensure that it is, first run the following command as the root user:
~]# yum install NetworkManager
5.1. The NetworkManager Daemon
The NetworkManager daemon runs with root privileges and is usually configured to start up at boot time. You can determine whether the NetworkManager daemon is running by entering this command as root:
~]# service NetworkManager status
NetworkManager (pid 1527) is running...
The service command will report NetworkManager is stopped if the NetworkManager service is not running. To start it for the current session:
~]# service NetworkManager start
Run the chkconfig command to ensure that NetworkManager starts up every time the system boots:
~]# chkconfig NetworkManager on
