man 8 NetworkManager-wait-online.service

NETWORKMANAGER-WAIT-ONLINENetwork management daemNETWORKMANAGER-WAIT-ONLINE(8)

NAME
       NetworkManager-wait-online.service - Wait for the network to come
       online

DESCRIPTION
       The NetworkManager-wait-online service is a oneshot systemd service
       that delays reaching the network-online target until NetworkManager
       reports that the startup is completed on the D-Bus.

       When the system boots, for example, remote mounts defined in
       /etc/fstab, require that the network is up. For this, these systemd
       units contain the After=network-online.target setting to order
       themselves after this target.  NetworkManager-wait-online ensures that
       the network-online target is reached only after the network is
       available.

       Optimally, all services on the host react dynamically to network
       changes and systemd services do not need to be configured to start
       after reaching the network-online target. In this case,
       NetworkManager-wait-online.service has no effect and does not delay the
       boot time. On the other hand, if you encounter a long boot time due to
       the delay of NetworkManager-wait-online, investigate the services that
       require network access and fix them.

       Except for the time out value in the NetworkManager-wait-online.service
       unit, you cannot configure this service. Instead, settings in
       NetworkManager and the connection profiles affect the behavior:

       o   Startup is not complete as long as NetworkManager profiles are in
           an activating state. During boot, NetworkManager starts profiles
           with the connection.autoconnect=yes setting. If activation fails,
           NetworkManager retries the activation depending on the value of the
           connection.autoconnect-retries setting.

           NetworkManager reports startup complete when all profiles and
           devices are either activated or in a disconnect state and no
           further events are expected.

       o   When a device reaches the activate state depends on its
           configuration. For example, with a profile that has both IPv4 and
           IPv6 enabled, by default, NetworkManager considers the device as
           fully activated already when only one of the address families is
           ready.

           The ipv4.may-fail and ipv6.may-fail settings control this behavior.
           Additionally, the following settings influence when the two address
           families complete: ipv4.required-timeout, ipv6.required-timeout,
           ipv4.dhcp-timeout, and ipv6.ra-timeout. For details, see nm-
           settings-nmcli(5).

       o   NetworkManager cannot set IP addresses on bridge and bond devices
           that have ports that do not auto-activate. Because of this
           configuration error, NetworkManager-wait-online blocks until the
           service reaches its timeout value.

       o   Dispatcher scripts for the pre-up event run at a late stage during
           activation of a profile. These scripts block the activation for
           when NetworkManager considers the profile fully activated. For
           details, see NetworkManager-dispatcher(8).

       o   The property connection.wait-activation-delay adds an additional
           delay during activation and delays startup complete. This setting
           works around certain cases where a device is known to not be ready
           for a certain amount of time.

       o   The property connection.wait-device-timeout in the connection
           profiles cause a delay until the waiting devices appear. This is
           useful if the driver takes a longer time to detect the networking
           interfaces. This setting is similar to the
           connection.gateway-ping-timeout property.

       o   With Wi-Fi devices, NetworkManager needs to wait for the first scan
           result to know which networks are available. That adds a delay.

       o   With Ethernet devices, NetworkManager waits for the carrier until
           the value in [device*].carrier-wait-timeout is reached. This is
           because some devices take a long time to detect the carrier.
           Consequently, booting with cable unplugged, unnecessarily delays
           NetworkManager-wait-online.service.

BUGS
       Please report any bugs in NetworkManager at the NetworkManager issue
       tracker[1].

SEE ALSO
       NetworkManager home page[2], NetworkManager(8), nm-online(1), the
       network-online.target description in systemd.special(7)

NOTES
        1. NetworkManager issue tracker
           https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues

        2. NetworkManager home page
           https://networkmanager.dev

NetworkManager-wait-online                       NETWORKMANAGER-WAIT-ONLINE(8)