1.3. Introduction to NetworkManager

In Red Hat Enterprise Linux 7, the default networking service is provided by NetworkManager, which is a dynamic network control and configuration daemon that attempts to keep network devices and connections up and active when they are available. The traditional ifcfg type configuration files are still supported. See Section 1.8, “NetworkManager and the Network Scripts” for more information.

Table 1.1. A Summary of Networking Tools and Applications

Application or ToolDescription
NetworkManagerThe default networking daemon
nmtuiA simple curses-based text user interface (TUI) for NetworkManager
nmcliA command-line tool provided to allow users and scripts to interact with NetworkManager
control-centerA graphical user interface tool provided by the GNOME Shell
nm-connection-editorA GTK+ 3 application available for certain tasks not yet handled by control-center
NetworkManager can configure network aliases, IP addresses, static routes, DNS information, and VPN connections, as well as many connection-specific parameters. NetworkManager provides an API through D-Bus which allows applications to query and control network configuration and state.
Finally, NetworkManager now maintains the state of devices after the reboot process and takes over interfaces which are set into managed mode during restart. In addition, NetworkManager can handle devices which are not explicitly set as unmanaged but controlled manually by the user or another network service.