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NETWORKMANAGER(8)                             Network management daemons                            NETWORKMANAGER(8)



NAME
       NetworkManager - network management daemon

SYNOPSIS
       NetworkManager [OPTIONS...]

DESCRIPTION
       The NetworkManager daemon attempts to make networking configuration and operation as painless and automatic as
       possible by managing the primary network connection and other network interfaces, like Ethernet, WiFi, and
       Mobile Broadband devices. NetworkManager will connect any network device when a connection for that device
       becomes available, unless that behavior is disabled. Information about networking is exported via a D-Bus
       interface to any interested application, providing a rich API with which to inspect and control network
       settings and operation.

DISPATCHER SCRIPTS
       NetworkManager will execute scripts in the /etc/NetworkManager/dispatcher.d directory or subdirectories in
       alphabetical order in response to network events. Each script should be a regular executable file owned by
       root. Furthermore, it must not be writable by group or other, and not setuid.

       Each script receives two arguments, the first being the interface name of the device an operation just
       happened on, and second the action. For device actions, the interface is the name of the kernel interface
       suitable for IP configuration. Thus it is either VPN_IP_IFACE, DEVICE_IP_IFACE, or DEVICE_IFACE, as
       applicable. For the hostname and connectivity-change actions it is always "none".

       The actions are:

       pre-up
           The interface is connected to the network but is not yet fully activated. Scripts acting on this event
           must be placed or symlinked into the /etc/NetworkManager/dispatcher.d/pre-up.d directory, and
           NetworkManager will wait for script execution to complete before indicating to applications that the
           interface is fully activated.

       up
           The interface has been activated.

       pre-down
           The interface will be deactivated but has not yet been disconnected from the network. Scripts acting on
           this event must be placed or symlinked into the /etc/NetworkManager/dispatcher.d/pre-down.d directory, and
           NetworkManager will wait for script execution to complete before disconnecting the interface from its
           network. Note that this event is not emitted for forced disconnections, like when carrier is lost or a
           wireless signal fades. It is only emitted when there is an opportunity to cleanly handle a network
           disconnection event.

       down
           The interface has been deactivated.

       vpn-pre-up
           The VPN is connected to the network but is not yet fully activated. Scripts acting on this event must be
           placed or symlinked into the /etc/NetworkManager/dispatcher.d/pre-up.d directory, and NetworkManager will
           wait for script execution to complete before indicating to applications that the VPN is fully activated.

       vpn-up
           A VPN connection has been activated.

       vpn-pre-down
           The VPN will be deactivated but has not yet been disconnected from the network. Scripts acting on this

       dhcp4-change
           The DHCPv4 lease has changed (renewed, rebound, etc).

       dhcp6-change
           The DHCPv6 lease has changed (renewed, rebound, etc).

       connectivity-change
           The network connectivity state has changed (no connectivity, went online, etc).

       The environment contains more information about the interface and the connection. The following variables are
       available for the use in the dispatcher scripts:

       CONNECTION_UUID
           The UUID of the connection profile.

       CONNECTION_ID
           The name (ID) of the connection profile.

       CONNECTION_DBUS_PATH
           The NetworkManager D-Bus path of the connection.

       CONNECTION_FILENAME
           The backing file name of the connection profile (if any).

       CONNECTION_EXTERNAL
           If "1", this indicates that the connection describes a network configuration created outside of
           NetworkManager.

       DEVICE_IFACE
           The interface name of the control interface of the device. Depending on the device type, this differs from
           DEVICE_IP_IFACE. For example for ADSL devices, this could be 'atm0' or for WWAN devices it might be
           'ttyUSB0'.

       DEVICE_IP_IFACE
           The IP interface name of the device. This is the network interface on which IP addresses and routes will
           be configured.

       IP4_ADDRESS_N
           The IPv4 address in the format "address/prefix gateway", where N is a number from 0 to (# IPv4 addresses -
           1). gateway item in this variable is deprecated, use IP4_GATEWAY instead.

       IP4_NUM_ADDRESSES
           The variable contains the number of IPv4 addresses the script may expect.

       IP4_GATEWAY
           The gateway IPv4 address in traditional numbers-and-dots notation.

       IP4_ROUTE_N
           The IPv4 route in the format "address/prefix next-hop metric", where N is a number from 0 to (# IPv4
           routes - 1).

       IP4_NUM_ROUTES
           The variable contains the number of IPv4 routes the script may expect.
           The same variables as for IPv4 are available for IPv6, but the prefixes are IP6_ and DHCP6_ instead.

       CONNECTIVITY_STATE
           The network connectivity state, which can take the values defined by the NMConnectivityState type, from
           the org.freedesktop.NetworkManager D-Bus API: unknown, none, portal, limited or full. Note: this variable
           will only be set for connectivity-change actions.

       In case of VPN, VPN_IP_IFACE is set, and IP4_*, IP6_* variables with VPN prefix are exported too, like
       VPN_IP4_ADDRESS_0, VPN_IP4_NUM_ADDRESSES.

       Dispatcher scripts are run one at a time, but asynchronously from the main NetworkManager process, and will be
       killed if they run for too long. If your script might take arbitrarily long to complete, you should spawn a
       child process and have the parent return immediately. Scripts that are symbolic links pointing inside the
       /etc/NetworkManager/dispatcher.d/no-wait.d/ directory are run immediately, without waiting for the termination
       of previous scripts, and in parallel. Also beware that once a script is queued, it will always be run, even if
       a later event renders it obsolete. (Eg, if an interface goes up, and then back down again quickly, it is
       possible that one or more "up" scripts will be run after the interface has gone down.)

OPTIONS
       The following options are understood:

       --version | -V
           Print the NetworkManager software version and exit.

       --help | -h
           Print NetworkManager's available options and exit.

       --no-daemon | -n
           Do not daemonize.

       --debug | -d
           Do not daemonize, and direct log output to the controlling terminal in addition to syslog.

       --pid-file | -p
           Specify location of a PID file. The PID file is used for storing PID of the running process and prevents
           running multiple instances.

       --state-file
           Specify file for storing state of the NetworkManager persistently. If not specified, the default value of
           /var/lib/NetworkManager/NetworkManager.state is used.

       --config
           Specify configuration file to set up various settings for NetworkManager. If not specified, the default
           value of /etc/NetworkManager/NetworkManager.conf is used with a fallback to the older
           'nm-system-settings.conf' if located in the same directory. See NetworkManager.conf(5) for more
           information on configuration file.

       --plugins
           List plugins used to manage system-wide connection settings. This list has preference over plugins
           specified in the configuration file. Currently supported plugins are: keyfile, ifcfg-rh, ifcfg-suse,
           ifupdown.

       --log-level
           Sets how much information NetworkManager sends to the log destination (usually syslog's "daemon"

       udev(7) device manager is used for the network device discovery. The following property influences how
       NetworkManager manages the devices:

       NM_UNMANAGED
           No default connection will be created and automatic activation will not be attempted when this property of
           a device is set to a true value ("1" or "true"). You will still be able to attach a connection to the
           device manually or observe externally added configuration such as addresses or routes.

           Create an udev rule that sets this property to prevent NetworkManager from interfering with virtual
           Ethernet device interfaces that are managed by virtualization tools.

SIGNALS
       NetworkManager process handles the following signals:

       SIGHUP
           The signal causes a reload of NetworkManager's configuration. Note that not all configuration parameters
           can be changed at runtime and therefore some changes may be applied only after the next restart of the
           daemon. A SIGHUP also involves further reloading actions, like doing a DNS update and restarting the DNS
           plugin. The latter can be useful for example when using the dnsmasq plugin and changing its configuration
           in /etc/NetworkManager/dnsmasq.d. However, it also means this will shortly interrupt name resolution. In
           the future, there may be further actions added. A SIGHUP means to update NetworkManager configuration and
           reload everything that is supported. Note that this does not reload connections from disk. For that there
           is a D-Bus API and nmcli's reload action

       SIGUSR1
           The signal forces a rewrite of DNS configuration. Contrary to SIGHUP, this does not restart the DNS plugin
           and will not interrupt name resolution. In the future, further actions may be added. A SIGUSR1 means to
           write out data like resolv.conf, or refresh a cache. It is a subset of what is done for SIGHUP without
           reloading configuration from disk.

       SIGUSR2
           The signal has no effect at the moment but is reserved for future use.

       An alternative to a signal to reload configuration is the Reload D-Bus call. It allows for more fine-grained
       selection of what to reload, it only returns after the reload is complete, and it is guarded by PolicyKit.

DEBUGGING
       The following environment variables are supported to help debugging. When used in conjunction with the
       --no-daemon option (thus echoing PPP and DHCP helper output to stdout) these can quickly help pinpoint the
       source of connection issues. Also see the --log-level and --log-domains to enable debug logging inside
       NetworkManager itself.

       NM_PPP_DEBUG: When set to anything, causes NetworkManager to turn on PPP debugging in pppd, which logs all PPP
       and PPTP frames and client/server exchanges.

SEE ALSO
       NetworkManager.conf(5), nmcli(1), nmcli-examples(7), nm-online(1), nm-settings(5), nm-applet(1), nm-
       connection-editor(1), udev(7)



NetworkManager 1.4.0                                                                                NETWORKMANAGER(8)