On Sun, Aug 6, 2023 at 6:32 PM aitor <aitor_czr@???> wrote:
>
> On 6/8/23 17:53, Manfred Wassmann via Dng wrote:
> >
> > It's part of the Posix standard so unless you're poettering won't go away
> > plus on Linux you also have ip from iproute2 as an alternative since
> > kernel version 2.2 and ...
>
> Poettering? ;~)

No, poettering.

> I have in mind to use the given code to setup my `/etc/network/interfaces` during
> the first boot.
>
> In a very early stage during the boot process none of those -Posix or non Posix-
> tools will work because network interfaces are still down or receiving packets.
> Do you remember the boot delay caused by ifupdown waiting for network?

Why? Interfaces don't need not be up to be able to get information. Try
# ifconfig eth0 down
# ifconfig eth0
and
# ip -a link show