"require" is a stronger version of "want",
and just like wantedBy allows you to specify this relation in reverse,
requiredBy does the same.
It may seem pointless to be able to specify these stronger relations in
reverse, because if something is really required, you would expect the
other unit to specify this himself.
However, this is still useful for virtual/automatic units (like
devices) that are created by systemd on demand and hence have no unit
file you can alter.
This allows Xen (and EC2) to power off an instance properly. We had
this before (see aeb89fc753c6f95c9d143e6f5346f92e4a02fa67), but it got
lost in the systemd migration.
Now that nixUnstable supports remounting in the "/nix/store is a
mountpoint" case, this is no longer necessary.
This reverts commit f1d48aec43947e5dddae8ba02e3133ee8d0d0ff9.
Signed-off-by: Shea Levy <shea@shealevy.com>
This makes it so multiple definitions are merged by adding a newline
between each entry, to avoid the need to add a newline to the end of
every definition of extraModprobeConfig. See #119 for an example of an
issue this has caused.
Signed-off-by: Shea Levy <shea@shealevy.com>
In principle this could work, but the current remount logic in nix fails
to remount mountpoints that are root in their own filesystem (as would
be the case with bind-mounting a mountpoint over itself). nixos/nix#98
is aimed at fixing this.
Signed-off-by: Shea Levy <shea@shealevy.com>
man logind.conf clearly states that the header is [Login] (no 'd').
Without this fix services.logind.extraConfig does not take effect
because logind ignores the invalidly named section.
So that we can customize systemd-logind in configuration.nix.
Example:
services.logind.extraConfig = "HandleLidSwitch=ignore";
See man logind.conf for available options.
EC2 instances don't have a console, so it's pointless to start
emergency mode if a mount fails. (This happened to me with an
encrypted filesystem where the key wasn't sent on time using "charon
send-keys".) Better to cross fingers and continue booting.
