On Sat, Oct 28, 2017 at 1:44 PM, Nikos Chantziaras <realnc@gmail.com> wrote:
>
> There is no such kernel option.

Yes, there is[1]. However, there is no such option for kernel version 4.9[2], although there is for 4.10[3]. I think that's the problem, for using the firewall BPF options of systemd, you'll need to use kernel version >= 4.10.