[systemd-devel] network-online.target is not down when a physical network is down

[Andrei Borzenkov]

В Thu, 22 Jan 2015 16:44:52 +0100
Igor Bukanov <igor at mir2.org> пишет:

> For a service that should be shutdown when network is not available, I
> tried to use Requires=network-online.target . However, on Fedora 21
> with NetworkManager that does not work. When I switch off WiFi, the
> only connection on my laptop that can configure default IP route and
> setup /etc/resolv.conf, network-online.target still stays active and
> my service continues to run. Is it a bug in Fedora? If not, what is a
> canonical way to implement such dependency?


No, it is not a bug. network-online was never intended to be used this
way. It was intended to be used only during startup; when initial
startup is finished, state of this service is largely irrelevant.

network-online.target itself does absolutely nothing. It is provided as
well known name for other services to order itself after; and you need
to provide implementation that orders itself before.

For NM implementation would be NetworkManager-wait-online.service that
basically does nothing more than calling nm-online.

Note that "network down" does not cause any change state in systemd.
NetworkManager still runs. systemd itself does not watch or manages
network, so it cannot initiate any actions here. I suppose you really
want to hook systemctl stop/systemctl start in NetworkManager
dispatcher framework.