This lets users do sneaky things before systemd starts, and
permanently affect the environment in which systemd runs. For example,
we could start systemd in a non-default network namespace by setting
the systemdExecutable to a wrapper script containing:
#!/bin/sh
ip netns add virtual
touch /var/run/netns/physical
mount -o bind /proc/self/ns/net /var/run/netns/physical
exec ip netns exec virtual systemd
_note: the above example does literally work, but there are unresolved
problems with udev and dhcp._
Also, add some sleep statements in between, which seems to at least feel
like it causes
> WARNING: Device /dev/vda* not initialized in udev database even after waiting 10000000 microseconds.
To occur less frequently.
This eventually still succeeds after some amount of waiting, I suspect
some racyness in the way lvm's udev-triggered scripts trigger other
units.
In the current implementation, there's no possibility to modify the default
parameter for keepalive. This is a number that indicates how frequently
keepalive messages should be sent from the worker to the buildmaster,
expressed in seconds. The default (600) causes a message to be sent to
the buildmaster at least once every 10 minutes.
If the worker is behind a NAT box or stateful firewall, these messages
may help to keep the connection alive: some NAT boxes tend to forget about
a connection if it has not been used in a while. When this happens, the
buildmaster will think that the worker has disappeared, and builds will
time out. Meanwhile the worker will not realize than anything is wrong.
This is required by (among others) Podman to run containers in rootless mode.
Other distributions such as Fedora and Ubuntu already set up these mappings.
The scheme with a start UID/GID offset starting at 100000 and increasing in 65536 increments is copied from Fedora.
Falling back to unversioned `/etc/fonts/conf.d` when versioned one does not exist
is problematic since it only occurs on non-NixOS systems and those are likely
to have a different version of fontconfig. When those versions use incompatible
elements in the config, apps using fontconfig will crash.
Instead, we are now falling back to the in-package `fonts.conf` file that loads
both the versioned global `conf.d` directory and the in-package `conf.d` since using
upstream settings on non-NixOS is preferable to not being able to use apps there.
In fact, we would not even need to link `fonts.conf`, as the in-package `fonts.conf`
will be always used unless someone creates the global one manually (the option is still
retained if one wants to write a custom NixOS module and to avoid unnecessary stat call on NixOS).
Additionally, since the `fonts.conf` will always load `conf.d` from the package, we no longer
need to install them to sytem `/etc` in the module. This needed some mucking with `50-user.conf`
which disables configs in user directories (a good thing IMO, NixOS module will turn it back on)
but otherwise, it is cleaner. The files are still prioritized by their name, regardless of their location.
See https://github.com/NixOS/nixpkgs/pull/73795#issuecomment-634370125 for more information.
This permits using method_set_hostname but still denies
method_set_static_hostname. As a result DHCP clients can now always set
the transient hostname via the SetHostname method of the D-Bus interface
of systemd-hostnamed (org.freedesktop.hostname1.set-hostname).
If the NixOS option networking.hostName is set to an empty string (or
"localhost") the static hostname (kernel.hostname but NOT /etc/hostname)
will additionally be updated (this is intended).
From "man hostnamectl": The transient hostname is a fallback value
received from network configuration. If a static hostname is set, and is
valid (something other than localhost), then the transient hostname is
not used.
Fix#74847.
Note: It's possible to restrict access to the org.freedesktop.hostname1
interface using Polkit rules.
This was broken in 460c0d6 (PR #90431); now the nixos-unstable channel
should get unblocked.
vcunat modified this commit to use env-var instead of hardcoding /build
Per upstream:
> libvirtd-tcp.socket - the unit file corresponding to the TCP 16509
> port for non-TLS remote access. This socket should not be configured
> to start on boot until the administrator has configured a suitable
> authentication mechanism.
