one usb calble for two nano's doing the exact same

Hi, How can I connect two nano's so that they do the same simultaneously with only one having an usb cable connected? Thanks

If you explain what it is that you want to do simultaneously someone may be able to suggest something.

One option that springs to mind is to use a 3rd Arduino (a Mega?) to connect to the PC and pass on messages by Serial to the two nanos.

...R

I have two boards doing the exact same and have a nano pin break out connector that connects one board to the other. For some reason that is not working out. Might solve that but I need a fallback scenario. I'd prefer a simple as possible solution and one USB from the pc. Let's call the nano that is connected to the pc master, what happens if the rx from the master is connected to the rx of the slave?

anatal:
what happens if the rx from the master is connected to the rx of the slave?

Nothing that you would notice.
But if you can resist having everything exactly the same, you might try having the two Nanos connected by software serial (master) and hardware serial (slave) Rx<>Tx and Tx<>Rx, and your master Nano connected to PC by USB as you describe you will have something that makes sense. The master can then pass on data from both Nanos to PC.

anatal:
I have two boards doing the exact same

What "exact same" thing?

Why does it need data from a PC?
Do the nanos need to send data to the PC?

Post the nano program.

what happens if the rx from the master is connected to the rx of the slave?

Data from the PC to the master should also appear on the RX pin of the slave. You must also have a GND connection between the nanos.

...R