Thanks guidol,
It's really working!
I would never thought it.
I spent the last 2 weeks fighting with the boot time (important for me) and now I suddenly lose 10 seconds.
Works with 5 s, but I do not like timers on the edge. I do not like to wait, no matter where.
There is no another (elegant) solution?
When booting, Linux should send short UDP broadcast datagram. It's all.
Thanks guidol again. It was helpful.