Example 10. of man page of systemd.network(5) shows:
```
Example 10. MacVTap
This brings up a network interface "macvtap-test" and attaches it to "enp0s25".
# /usr/lib/systemd/network/25-macvtap.network
[Match]
Name=enp0s25
[Network]
MACVTAP=macvtap-test
```
Which is a MACVTAP example and is currently unsupported in NixOS.
This is useful for people using "modern" technologies with virtual machines.
The whole option set was recommended against since mid-2019, and never
worked with the Raspberry Pi 4 family of devices.
We should have deprecated it in early 2020 for removal by 2021. At the
time I did not feel confident in making such a decision, and never
ended-up getting around to it.
The ***only*** supported-by-NixOS boot methods for AArch64 are
standards-based boot methods, namely UEFI or the pragmatically
almost-standard extlinux-compatible for U-Boot.
You can quote me on that.
These variables were previously used by the activation script
build commands, but are now embedded into those commands for
to improve reusability for an upcoming addition.
This helps with understanding the code.
We might make this not depend on environment variables later.
systemBuilderArgs is a form of global state, which isn't helpful.
This essentially backports
https://github.com/systemd/systemd/pull/27791. `systemd-networkd.service`
is sent the `SIGTERM` signal, but it is not required to be stopped
before `initrd-switch-root.target` is reached, despite the use of
`systemctl isolate initrd-switch-root.target`. This is because when
there is no ordering at all between two units, and a transaction stops
one and starts the other, the two operations can happen
simultaneously. This means the service could still be running when
`switch-root` actually occurs. Then, stage 2 systemd will see the
service still running and decide it doesn't need to add a start
operation for it to its initial transaction. Finally, the service
exits, but only after it's already too late. If, however, there is any
ordering at all between a stopping unit and a starting unit, then the
stop operation will be done first. This way, we ensure that the
service is properly exited before doing `switch-root`.
This is something to keep in mind going forward. There may be other
services that need this treatment. These `before` and `conflicts`
definitions are the correct way to ensure a unit is actually stopped
before you reach initrd-switch-root
This patch fixes "Argument list too long" build failure when passing a
list of store paths to system.extraDependencies that exceeds Linux'
MAX_ARG_STRLEN limit of 128 KiB. With the shortest possible derivation
names (one byte), the 128 KiB limit is equivalent to about 2850
derivations. With longer derivations names, the limit is hit earlier.
Fix this restriction.
it is now possible to supply a stratis pool uuid
for every filesystem, and if that filesystem
is required for boot, the relevant pool will be
started in the initramfs.
Enable using an erofs filesystem as one of the filesystems needed to
boot the system. This is useful for example in image based deployments
where the Nix store is mounted read only.
[erofs](https://docs.kernel.org/filesystems/erofs.html) offers multiple
benefits over older filesystems like squashfs. Skip fsck.erofs because
it is still experimental.
Note that this does not add to the `forbiddenDependenciesRegex`
code because that code check should be unaffected as it only checks
output dependencies, not build dependencies.
Build deps are added after that check, if those are enabled in the
first place.
