Contents
NetworkManager is the ideal solution for laptops and other portable computers. It supports state-of-the-art encryption types and standards for network connections, including connections to 802.1X protected networks. 802.1X is the “IEEE Standard for Local and Metropolitan Area Networks—Port-Based Network Access Control”. With NetworkManager, you do not need to worry about configuring network interfaces and switching between wired or wireless networks when you are moving. NetworkManager can automatically connect to known wireless networks or manage several network connections in parallel—the fastest connection is then used as default. Furthermore, you can manually switch between available networks and manage your network connection using an applet in the system tray.
Instead of only one connection being active, multiple connections may be active at once. This enables you to unplug your laptop from an Ethernet and remain connected via a wireless connection.
NetworkManager provides a sophisticated and intuitive user interface, which enables users to easily switch their network environment. However, NetworkManager is not a suitable solution in the following cases:
Your computer provides network services for other computers in your network, for example, it is a DHCP or DNS server.
Your computer is a Xen server or your system is a virtual system inside Xen.
On laptop computers, NetworkManager is enabled by default. However, it can be at any time enabled or disabled in the YaST Network Settings module.
Run YaST and go to
+ .The
dialog opens. Go to the tab.To configure and manage your network connections with NetworkManager, select
.Click
.After choosing the method for managing network connections, set up your network card using automatic configuration via DHCP or a static IP address or configure your modem (for dial-up connections, use
+ ). To configure an internal or USB ISDN modem, select + . To configure an internal or USB DSL modem, select + .Find a detailed description of the network configuration with YaST in Section “Configuring a Network Connection with YaST” (Chapter 21, Basic Networking, ↑Reference) and Chapter Wireless LAN (↑Reference).
After having enabled NetworkManager, configure your network connections with the NetworkManager as described in Section 5.3, “Configuring Network Connections”.
If you want to deactivate NetworkManager and control network the traditional way, choose the
option in the field.After having enabled NetworkManager in YaST, configure your network connections with the NetworkManager front-ends available in KDE and GNOME. The network configuration dialogs for both front-ends are very similar. They show tabs for all types of network connections, such as wired, wireless, mobile broadband, DSL, and VPN connections. On each tab, you can add, edit or delete connections of that type. In the KDE configuration dialog, the appropriate tabs are only active if the connection type is available on your system (depending on hardware and software). By default, KNetworkManager also displays comprehensive tooltips for the input fields and options available on each tab.
To open the network configuration dialog in GNOME, press Alt+F2 and enter nm-connection-editor or in the GNOME Control Center select + .
If you use KDE, open the main menu and click
. In the then select on the tab to open the network configuration dialog.Alternatively, you can also start the configuration dialogs from the NetworkManager applet in the system tray. In KDE, left-click the icon and select
. In GNOME, right-click the icon and select .![]() | Availability of Options |
---|---|
Depending on your system set-up, you may not be allowed to configure
connections. In a secured environment, some options might be locked or
require |
Procedure 5.1. Adding or Editing Connections
When configuring network connections with NetworkManager, you can also define
system connections
that can be shared by all users.
In contrast to user connections
, system connections
are made available right after NetworkManager is started—before any users
log in. For more details about both types of connections, refer to
Section 5.7.1, “User and System Connections”.
Currently, the system connection
option is not
available in KNetworkManager. To set up system connections, you need to use YaST
in this case.
![]() | Hidden Networks |
---|---|
To connect to a “hidden” network (a network that does not broadcast its service) you have to know the Service Set Identifier or Extended Service Set Identifier (SSID or ESSID) of the network because it cannot be detected automatically. |
To add a new connection, click the tab for the connection type you want to use and click
.Enter a
and your connection details.For a hidden network, enter the (E)SSID and in the
tab the encryption parameters.You can tie the connection to a certain device, if more than one physical device per connection type is available (for example, your machine is equipped with two ethernet cards or two wireless cards).
If you use KDE, do so by using the
option. If you use GNOME, enter the of the device you want to tie the connection to and confirm your settings.If you want NetworkManager to automatically use a certain connection, activate
for this connection.
To turn a connection into a system connection
activate (GNOME). To create
and edit system connections, root
permission is required.
After having confirmed your changes, the newly configured network connection appears in the list of available networks you get by left-clicking the NetworkManager applet.
At the moment, Bluetooth connections cannot be configured with NetworkManager.
The KDE front-end for NetworkManager is the KNetworkManager applet. If the network has been set up for NetworkManager control, the applet usually starts automatically with the desktop environment and is shown as an icon in the system tray.
If your system tray does not show any network connection icon, the applet is probably not started. Press Alt+F2 and enter knetworkmanager to start it manually.
KNetworkManager only shows wireless networks that you have configured a connection for. It hides connections when you are out of range of a wireless network, or when the network cable is disconnected, thus always giving you a clear view of which connections may be used.
If your computer is connected to an existing network with a network cable, use KNetworkManager to choose the network connection.
Left-click the applet icon to show a menu with available networks. The connection currently being used is selected in the menu and marked as
.If you want to use a different configuration with the wired network, click Procedure 5.1, “Adding or Editing Connections”.
and add another wired connection as described inClick the KNetworkManager icon and select the newly configured connection to activate it.
By default, KNetworkManager only shows wireless networks that you have configured a connection for—provided they are both available and visible. To connect to a wireless network for the first time, proceed as follows:
Left-click the applet icon and select
. KNetworkManager shows a list of available visible wireless networks, including details about signal strength and security.To connect to a visible network, select the network from the list and click
. If the network is encrypted, a dialog opens. Choose the type of the network uses and enter the appropriate credentials.To connect to a network that does not broadcast its service set identifier ((E)SSID) and therefore cannot be detected automatically, select
.In the dialog that opens, enter the ESSID and set encryption parameters, if necessary.
Confirm your changes and click
. NetworkManager now activates the new connection.To terminate a connection and to disable wireless networking, click the applet icon and uncheck
. This can be useful if you are on a plane or in any other environment where wireless networking is not allowed.A wireless network that has been chosen explicitly will remain connected as long as possible. If a network cable is plugged in during that time, any connections that have been set to
will be connected, while the wireless connection remains up.If your wireless card supports access point mode, you can use NetworkManager for configuration.
![]() | Availability of Options |
---|---|
Depending on your system set-up, you may not be allowed to configure
connections. In a secured environment, some options might be locked or
require |
Click the KNetworkManager applet and select
+ .In the following configuration dialog, enter a name for your network in the
field.![]() |
Set the encryption on the
tab.![]() | Unprotected Wireless Networks Are a Security Risk |
---|---|
If you set |
On the
tab, make sure the option is set to (which is the default option for ad-hoc networks).Confirm your configuration with
.You can customize some aspects of KNetworkManager: the number of icons displayed in the system tray, which tool tips to show and how to store your password and credentials for network connections. For more information about the last aspect, refer to Section 5.7.2, “Storing Passwords and Credentials”.
To explore the options available, start the
from the main menu, select on the tab and click on the left-hand side of the configuration dialog.Procedure 5.2. Configuring Multiple Tray Icons for KNetworkManager
As KNetworkManager can keep multiple connections active at once, you might wish to be informed about the connection status for several connections at one glance. You can do so by using multiple NetworkManager icons in your system tray, each representing a different group of connection types (for example, one icon for wired connections, another icon for wireless connections).
In the configuration dialog, switch to the
tab.Click
. A new icon entry appears in the list.Select the network connection types you want to be represented by this icon and group them under the respective icon.
![]() |
Confirm your changes.
Now the system tray shows multiple NetworkManager icons from which you then can access the connection types tied to that icon.
When configuring a network connection as described in Procedure 5.1, “Adding or Editing Connections”, KNetworkManager also allows you to customize the icon displayed for this connection. To change the icon, click the icon button next to and in the following dialog, select the icon of your choice. After confirming your changes, the new icon is displayed in the list of available connections you get by clicking the KNetworkManager icon in the system tray.
In GNOME, NetworkManager can be controlled with the GNOME NetworkManager applet. If the network is set up for NetworkManager control, the applet usually starts automatically with the desktop environment and is shown as an icon in the system tray.
If your system tray does not show any network connection icon, the applet is probably not started. Press Alt+F2 and enter nm-applet to start it manually.
If your computer is connected to an existing network with a network cable, use the NetworkManager applet to choose the network connection.
Left-click the applet icon to show a menu with available networks. The currently used connection is selected in the menu.
To switch to another network, choose it from the list.
To switch off all network connections, both wired and wireless, right-click the applet icon and uncheck
.Available visible wireless networks are listed in the GNOME NetworkManager applet menu under
. The signal strength of each network is also shown in the menu. Encrypted wireless networks are marked with a shield icon.Procedure 5.3. Connecting to a Wireless Network
To connect to a wireless network, left-click the applet icon and choose an entry from the list of available wireless networks.
If the network is encrypted, a dialog opens. It shows the type of encryption the network uses (
) and holds a number of input fields according to the respective encryption and authentication settings. Enter the appropriate credentials.To connect to a network that does not broadcast its service set identifier ((E)SSID) and therefore cannot be detected automatically, left-click the NetworkManager icon and choose
.In the dialog that opens, enter the ESSID and set encryption parameters on the
tab if necessary.To disable wireless networking, right-click the applet icon and uncheck
. This can be useful if you are on a plane or in any other environment where wireless networking is not allowed.A wireless network that has been chosen explicitly will remain connected as long as possible. If a network cable is plugged in during that time, any connections that have been set to
will be connected, while the wireless connection remains up.If your wireless card supports access point mode, you can use NetworkManager for configuration.
![]() | Availability of Options |
---|---|
Depending on your system set-up, you may not be allowed to configure
connections. In a secured environment, some options might be locked or
require |
Click the NetworkManager applet and select
.![]() |
Enter a
and set the encryption to use with the drop-down list.![]() | Unprotected Wireless Networks Are a Security Risk |
---|---|
If you set |
NetworkManager supports several Virtual Private Network (VPN) technologies. For each technology, openSUSE comes with a base package providing the generic support for NetworkManager. In addition to that, you also need to install the respective desktop-specific package for your applet.
To use this VPN technology, install
NetworkManager-novellvpn
and
NetworkManager-novellvpn-kde4
or
NetworkManager-novellvpn-gnome
.
NovellVPN support for KDE is not available yet, but is currently being worked on.
To use this VPN technology, install
NetworkManager-openvpn
and
NetworkManager-openvpn-kde4
or
NetworkManager-openvpn-gnome
.
To use this VPN technology, install
NetworkManager-vpnc
and
NetworkManager-vpnc-kde4
or
NetworkManager-vpnc-gnome
.
To use this VPN technology, install
NetworkManager-pptp
and
NetworkManager-pptp-kde4
or
NetworkManager-pptp-gnome
.
After you have installed the packages, configure your VPN connection as described in Section 5.3, “Configuring Network Connections”.
NetworkManager distinguishes two types of wireless connections, trusted and untrusted. A trusted connection is any network that you explicitly selected in the past. All others are untrusted. Trusted connections are identified by the name and MAC address of the access point. Using the MAC address ensures that you cannot use a different access point with the name of your trusted connection.
NetworkManager periodically scans for available wireless networks. If multiple trusted networks are found, the most recently used is automatically selected. NetworkManager waits for your selection in case that all networks are untrusted.
If the encryption setting changes but the name and MAC address remain the same, NetworkManager attempts to connect, but first you are asked to confirm the new encryption settings and provide any updates, such as a new key.
If you switch from using a wireless connection to offline mode, NetworkManager blanks the ESSID. This ensures that the card is disconnected.
NetworkManager knows two types of connections: user
and
system
connections. User connections are connections
that become available to NetworkManager when the first user logs in. Any required
credentials are asked from the user and when the user logs out, the
connections are disconnected and removed from NetworkManager. Connections that are
defined as system connection can be shared by all users and are made
available right after NetworkManager is started—before any users log in. In
case of system connections, all credentials must be provided at the time
the connection is created. Such system connections can be used to
automatically connect to networks that require authorization. For
information how to configure user or system connections with NetworkManager, refer
to Section 5.3, “Configuring Network Connections”.
For KDE, system connections with NetworkManager are currently not supported (use YaST instead).
If you do not want to re-enter your credentials each time you want to connect to an encrypted network, you can use the desktop-specific tools GNOME Keyring Manager or KWalletManager to store your credentials encrypted on the disk, secured by a master password.
With KNetworkManager, you can configure if and how to store your credentials in KDE. To do so, left-click the KNetworkManager icon and select
. Click + and select one of the following options:This is useful if you are working in an environment where storing credentials is considered a security risk.
![]() | Security Risk |
---|---|
Storing your network credentials unencrypted is a security risk. Everybody who has access to your computer can reuse your connectivity and intercept your network connection. |
If you choose this option, your passwords are stored unencrypted in
the respective connection file that is created for each connection.
Find them under
$HOME/.kde4/share/apps/networkmanagement/connections
.
If you choose this options, your credentials are stored in KWalletManager. For more information on KWalletManager, see Chapter Managing Passwords with KWallet Manager (↑KDE User Guide).
In the following, find some frequently asked questions about configuring special network options with NetworkManager.
By default, connections in NetworkManager are device type-specific: they apply to all physical devices with the same type. If more than one physical device per connection type is available (for example, your machine is equipped with two ethernet cards), you can tie a connection to a certain device.
To do so in GNOME, first look up the MAC address of your device (use the nm-tool or ifconfig). Then start the dialog for configuring network connections and choose the connection you want to modify. On the or tab, enter the of the device and confirm your changes.
available from the applet, or use the output of command line tools likeIf you use KDE, start the dialog for configuring network connections and choose the connection you want to modify. On the
or tab, use the option to select the network interface to which to tie the connection.When multiple access points with different wireless bands (a/b/g/n) are available, the access point with the strongest signal is automatically chosen by default. To override this, use the
field when configuring wireless connections.The Basic Service Set Identifier (BSSID) uniquely identifies each Basic Service Set. In an infrastructure Basic Service Set, the BSSID is the MAC address of the wireless access point. In an independent (ad-hoc) Basic Service Set, the BSSID is a locally administered MAC address generated from a 46-bit random number.
Start the dialog for configuring network connections from the GNOME Control Center with
+ or in KDE 4 from the with . Choose the wireless connection you want to modify and click . On the tab, enter the BSSID.The primary device (the device which is connected to the Internet) does not need any special configuration. However, you need to configure the device that is connected to the local hub or machine as follows:
Start the dialog for configuring network connections from the GNOME Control Center with
+ or in KDE 4 from the with + . Choose the connection you want to modify and click . If you are using GNOME, switch to the tab and from the drop-down list, choose . If you are using KDE, switch to the tab and from the drop-down list, choose . That will enable IP traffic forwarding and run a DHCP server on the device. Confirm your changes in NetworkManager.As the DCHP server uses port 67, make sure that it is not blocked by the firewall: On the machine sharing the connections, start YaST and select
+ . Switch to the category. If is not already shown as , select from and click . Confirm your changes in YaST.In case a DHCP server provides invalid DNS information (and/or routes), you can override it. Start the dialog for configuring network connections from the GNOME Control Center with
+ or in KDE 4 from the with + . Choose the connection you want to modify and click . If you are using GNOME, switch to the tab, and from the drop-down list, choose . If you are using KDE, switch to the tab, and from the drop-down list, choose . Enter the DNS information in the and fields. From the drop-down list at the bottom of the tab, select if you want to . Confirm your changes.
Define a system connection
that can be used for
such purposes. For more information, refer to
Section 5.7, “NetworkManager and Security”.
Connection problems can occur. Some common problems related to NetworkManager include the applet not starting or a missing VPN option. Methods for resolving and preventing these problems depend on the tool used.
The GNOME and KDE NetworkManager applets start automatically if the network is
set up for NetworkManager control. If the applet does not start, check if NetworkManager
is enabled in YaST as described in
Section 5.2, “Enabling NetworkManager”. Then make sure that the appropriate
package for your desktop environment is also installed. If you are
using KDE 4, the package is
NetworkManager-kde4
. For GNOME
users the package is
NetworkManager-gnome
.
If the desktop applet is installed but is not running for some reason, start it manually with the command nm-applet (GNOME) or knetworkmanager (KDE).
Support for NetworkManager, applets, and VPN for NetworkManager is distributed in separate packages. If your NetworkManager applet does not include the VPN option, check if the packages with NetworkManager support for your VPN technology are installed. For more information, see Section 5.6, “NetworkManager and VPN”.
If you have configured your network connection correctly and all other
components for the network connection (router, etc.) are also up and
running, it sometimes helps to restart the network interfaces on your
computer. To do so, log in to a command line as root
and run
rcnetwork restart.
More information about NetworkManager can be found on the following Web sites and directories:
Also check out the information in the following directories for the latest information about NetworkManager and the GNOME and KDE NetworkManager applets:
/usr/share/doc/packages/NetworkManager/
,
/usr/share/doc/packages/NetworkManager-kde4/
,
and
/usr/share/doc/packages/NetworkManager-gnome/
.