The triggers are just arbitrary strings that are included in the unit
under X-Restart-Triggers. The idea is that if they change between
reconfigurations, switch-to-configuration will restart the unit
because its store path changed. This is mostly useful for services
that implicitly depend on generated files in /etc. Thus you can say
restartTriggers = [ confFile ];
where ‘confFile’ is the derivation that generated the /etc file in
question.
For each statically configured interface, we now create a unit
‘<interface>-cfg.service’ which gets started as soon as the network
device comes up. Similarly, each bridge defined in
‘networking.bridges’ and virtual interface in ‘networking.interfaces’
is created by a service ‘<interface>.service’.
So if we have
networking.bridges.br0.interfaces = [ "eth0" "eth1" ];
networking.interfaces =
[ { name = "br0";
ipAddress = "192.168.1.1";
}
];
then there will be a unit ‘br0.service’ that depends on
‘sys-subsystem-net-devices-eth0.device’ and
‘sys-subsystem-net-devices-eth1.device’, and a unit ‘br0-cfg.service’
that depends on ‘sys-subsystem-net-devices-br0.device’.
It's not enough to say "after udev-settle.service" since
udev-settle.service is not wanted/required anywhere - we need to say
"wants udev-settle.service" as well.
This should fix problems with ALSA and X11 initialisation that people
have been seeing.
So instead of:
boot.systemd.services."foo".serviceConfig =
''
StartLimitInterval=10
CPUShare=500
'';
you can say:
boot.systemd.services."foo".serviceConfig.StartLimitInterval = 10;
boot.systemd.services."foo".serviceConfig.CPUShare = 500;
This way all unit options are available and users can set/override
options in configuration.nix.
Systemd sets locale variables like $LANG when running services, so
$LOCALE_ARCHIVE should also be set to prevent warnings like "perl:
warning: Setting locale failed.".
kernel 3.4+ needs cifs-utils to mount CIFS filesystems.
the kernel itself (and busybox's cifs mount code) are no longer able
to do this in some/most cases and will error out saying:
"CIFS VFS: connecting to DFS root not implemented yet"
Nixos' qemu-vm target is hurt by this, as it wants to mount /nix/store
via cifs very early in the boot process.
This commit makes sure the initrd for affected kernels is built with
cifs-utils if needed.
If a service has a corresponding socket unit, then stop the socket
before stopping the service. This prevents it from being restarted
behind our backs. Also, don't restart the service; it will be
restarted on demand via the socket.
Subtle: dhcpcd.service would call resolvconf during shutdown, which in
turn would start invalidate-nscd.service, causing the shutdown to be
cancelled. Instead, give nscd.service a proper reload action, and do
"systemctl reload --no-block nscd.service". The --no-block is
necessary to prevent that command from waiting until a timeout occurs
(bug in systemd?).
