Can't get connection for second Ethernet card

[DevilInPgh]

That didn't help. Moreover, when I attempted to create a second profile and put the MAC address of the Roku box in the entry, it fails to show up under the nm-applet icon under either card, so there is no way of starting it. At least I hope I'm right in putting the Roku's MAC address in the connection entry.

[wise_crypt]

type sudo iptables -L and pastebin it please
this link https://help.ubuntu.com/community/In...nectionSharing << might also help you to share your connections