Provided by: network-manager_1.36.6-0ubuntu2.1_amd64 
NAME
nm-online - ask NetworkManager whether the network is connected
SYNOPSIS
nm-online [OPTIONS...]
DESCRIPTION
nm-online is a utility to find out whether we are online. It is done by asking NetworkManager about its
status. When run, nm-online waits until NetworkManager reports an active connection, or specified timeout
expires. On exit, the returned status code should be checked (see the return codes below).
This tool is not very useful to call directly. It is however used by NetworkManager-wait-online.service
with --wait-for-startup argument. This is used to delay the service and indirectly network-online.target,
until networking is up. Don't order your own systemd services after NetworkManager-wait-online.service
directly. Instead if necessary, order your services after network-online.target. Even better is to have
your services react to network changes dynamically and don't order them with respect to
network-online.target at all.
By default, connections have the ipv4.may-fail and ipv6.may-fail properties set to yes; this means that
NetworkManager waits for one of the two address families to complete configuration before considering the
connection activated. If you need a specific address family configured before network-online.target is
reached, set the corresponding may-fail property to no.
OPTIONS
-h | --help
Print help information.
-q | --quiet
Don't print anything.
-s | --wait-for-startup
Wait for NetworkManager startup to complete, rather than waiting for network connectivity
specifically. Startup is considered complete once NetworkManager has activated (or attempted to
activate) every auto-activate connection which is available given the current network state. This
corresponds to the moment when NetworkManager logs "startup complete". This mode is generally only
useful at boot time. After startup has completed, nm-online -s will just return immediately,
regardless of the current network state.
There are various ways to affect when startup complete is reached. For example, by setting a
connection profile to autoconnect, such a profile possibly will activate during startup and thus
delay startup complete being reached. Also, a profile is considered ready when it fully reached the
logical connected state in NetworkManager. That means, properties like ipv4.may-fail and
ipv6.may-fail affect whether a certain address family is required. Also, the connection property
connection.wait-device-timeout affects whether to wait for the driver to detect a certain device.
Generally, a failure of NetworkManager-wait-online.service indicates a configuration error, where
NetworkManager won't be able to reach the desired connectivity state during startup. An example for
that are bridge or bond master profiles, that get autoconnected but without activating any slaves.
Such master devices hang in activating state indefinitely, and cause
NetworkManager-wait-online.service to fail.
-t | --timeout seconds
Time to wait for a connection, in seconds. If the option is not provided, the environment variable
NM_ONLINE_TIMEOUT is honored. The default timeout is 30 seconds.
-x | --exit
Exit immediately if NetworkManager is not running or connecting.
EXIT STATUS
nm-online exits with status 0 if it succeeds, a value greater than 0 is returned if an error occurs.
0
Success – already online or connection established within given timeout.
1
Offline or not online within given timeout.
2
Unknown or unspecified error.
SEE ALSO
nmcli(1), NetworkManager(8).