In some cases like we've noticed in https://github.com/NixOS/nixpkgs/issues/76169,
having duplicate packages in systemd.packages like
```
systemd.packages = [ gnome-shell gnome-shell gnome-session ];
```
breaks.
Here we use an associative array to ensure no
duplicate paths when we symlink all the units listed
in systemd.packages.
This fixes the dhcpcd issue in https://github.com/NixOS/nixpkgs/issues/76969,
which was exposed by https://github.com/NixOS/nixpkgs/pull/75031
introducing changes in the module ordering and therefore option ordering
too.
The dhcpcd issue would also be fixable by explicitly putting
dhcpcd's paths before others, however it makes more sense for systemd's
default paths to be after all others by default, since they should only
be a fallback, which is how binary finding will work if they come after.
When using a modified systemd-package (e.g. to test a patch), it's
recommended to use the `systemd.package`-option to avoid rebuilding all packages
that somehow depend on systemd.
With this change, the modified package is also used by `systemd-nspawn@`
units.
A centralized list for these renames is not good because:
- It breaks disabledModules for modules that have a rename defined
- Adding/removing renames for a module means having to find them in the
central file
- Merge conflicts due to multiple people editing the central file
The options at `systemd.network` (`links`, `netdevs` and `networks`) are
directly mapped to the three different unit types of `systemd-networkd(8)`.
However there's also the option `systemd.network.units` which is
basically used as a container for generated unit-configs that are linked
to `/etc/systemd/networkd`[1].
This should not be exposed to the user as it's unclear whether or not it
should be used directly which can be pretty confusing which is why I decided to
declare this option as internal (including all sub-options as `internal`
doesn't seem to be propagated to submodules).
[1] 9db75ed88f/nixos/modules/system/boot/networkd.nix (L933-L937)
Previously, socket units wouldn't be restarted if they were
changed. To restart the socket, the service the socket is attached
to needs to be stopped first before the socket can be restarted.
This adds an `extraConfig` option to timesyncd for setting additional
options in `/etc/systemd/timesyncd.conf`.
This is similar to things like `services.journald.extraConfig` and
`services.logind.extraConfig`.
This has been there since v209 [1]
```
The interface name to use. This option has lower precedence than NamePolicy=, so for this setting to take effect, NamePolicy= must either be unset, empty, disabled, or all policies configured there must fail. Also see the example below with "Name=dmz0".
Note that specifying a name that the kernel might use for another interface (for example "eth0") is dangerous because the name assignment done by udev will race with the assignment done by the kernel, and only one interface may use the name. Depending on the order of operations, either udev or the kernel will win, making the naming unpredictable. It is best to use some different prefix, for example "internal0"/"external0" or "lan0"/"lan1"/"lan3".
```
[1] 43b3a5ef61
Adding `systemd-importd` to the build, so that `machinectl`s `import-.*`
may actually do anything. Currently they fail with
```
Failed to transfer image: The name org.freedesktop.import1 was not provided by any .service files
```
as `systemd-importd` is not built. Also registers the regarding dbus
api and service in the systemd module.
Both options were introduced in systemd v243[1]. Those options can be
used to ensure that LinkLocalAddressing is only configured for a given
interface if DHCPv4 fails. To quote `systemd.network(5)`:
```
If "fallback" or "ipv4-fallback" is specified, then an IPv4
link-local address is configured only when DHCPv4 fails. If "fallback", an IPv6 link-local
address is always configured, and if "ipv4-fallback", the address is not configured. Note
that, the fallback mechanism works only when DHCPv4 client is enabled, that is, it requires
"DHCP=yes" or "DHCP=ipv4".
```
[1] 8bc17bb3f7
GDM now specifies ordering between `plymouth-quit` and `display-manager`:
9be5321097
This causes an ordering cycle between GDM and plymouth-quit which can result in
systemd breaking GDM:
```
plymouth-quit.service: Job display-manager.service/start deleted to break
ordering cycle starting with plymouth-quit.service/start
```
Not sure how often this triggers, as I've run my system with plymouth and
9be5321097 without any issues. But I did catch a VM doing this.
NOTE: I also tried to remove the ordering in GDM to see if plymouth managed to
live longer, but it didn't seem to help. So I opted to stick as close to
upstream (upstream GDM specifies ordering, but plymouth does not).
Images generated with nixos-install will be supported by machinectl
problem is that systemd-nspawn's private usersns feature clashes
with DynamicUser and RuntimeDirectory features, which causes NixOS
images to not boot. There is an upstream issue for this
https://github.com/systemd/systemd/issues/13622
