[systemd-devel] how to automate undirected UDP broadcast route for linklocal addresses?

[Lennart Poettering]

On Mo, 10.06.24 13:52, Bill Plunkett (bill at plunkware.com) wrote:

> I have a yocto-hardknott (systemd v247) embedded system using link local
> addressing.  Undirected UDP broadcasts (i.e. dest ip = 255.255.255.255) are
> failing with a 'Network is unreachable' error.  I've been able to fix this
> with the 'route add' command shown below, but would prefer to automate it
> with systemd.  Any help is greatly appreciated.
>
> This command allows undirected broadcasts:
>
> route add -net 255.255.255.255 netmask 255.255.255.255 dev eth0
>
> systemd configuration:
>
> [Match]
> Name=eth0
> KernelCommandLine=!nfsroot
>
> [Network]
> DHCP=ipv4
> LinkLocalAddressing=ipv4
>
> [DHCP]
> ClientIdentifier=mac
> RouteMetric=10


It should suffice adding the following to your .network file:

    [Route]
    Destination=255.255.255.255/32

Lennart

--
Lennart Poettering, Berlin