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 action 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 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 VPN
           from its network. Note that this event is not emitted for forced disconnections, like when the VPN
           terminates unexpectedly or general connectivity is lost. It is only emitted when there is an
           opportunity to cleanly handle a VPN disconnection event.

       vpn-down
           A VPN connection has been deactivated.

       hostname
           The system hostname has been updated. Use gethostname(2) to retrieve it. The interface name (first
           argument) is empty and no environment variable is set for this action.

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

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

       IP4_NAMESERVERS
           The variable contains a space-separated list of the DNS servers.

       IP4_DOMAINS
           The variable contains a space-separated list of the search domains.

       DHCP4_<dhcp-option-name>
           If the connection used DHCP for address configuration, the received DHCP configuration is passed in
           the environment using standard DHCP option names, prefixed with "DHCP4_", like
           "DHCP4_HOST_NAME=foobar".

       IP6_<name> and DHCP6_<name>
           The same variables as for IPv4 are available for IPv6, but the prefixes are IP6_ and DHCP6_ instead.

       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"
           facility). By default, only informational, warning, and error messages are logged. See the section on
           logging in NetworkManager.conf(5) for more information.

       --log-domains
           A comma-separated list specifying which operations are logged to the log destination (usually
           syslog). By default, most domains are logging-enabled. See the section on logging in
           NetworkManager.conf(5) for more information.

       --print-config
           Print the NetworkManager configuration to stdout and exit.

UDEV PROPERTIES

       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 1.2.6                                                                           NETWORKMANAGER(8)