Thank you for contacting Intel.
The Intel® Ethernet Server Adapters with fiber optic connector requires that RX and TX ports be connected. The network adapter won't connect when only 1 port (RX or TX) is connected.
Thanks for the feedback. Could you please let me know if some other (desktop?) Intel cards would allow one way hookup? Is this limitation a question of the driver or the hardware/firmware? Since now cybersecurity is becoming ever so important, it would be an elegant and easy solution to use fiber optic cards as a data diode.
Thanks for writing back.
Currently, all our fiber optic Ethernet Adapters requires both RX and TX port connected in order to work. You will need a specialized fiber optic card to use it as a data diode.
I have noted your concerns to consider it for our future product release.
Feel free to contact us if you further questions regarding Intel Network Cards.