NAME
NetworkManager-wait-online.service - Wait for the network to come onlineDESCRIPTION
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:•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.
•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).
•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.
•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).
•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.
•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.
•With Wi-Fi devices, NetworkManager
needs to wait for the first scan result to know which networks are available.
That adds a delay.
•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
- 2.
- NetworkManager home page
| NetworkManager-wait-online |