This is one of those occasions for the Staple's "That was easy" button.
Right-click on the network icon
Select Eth[your secondary port]
Change the name to ICS or whatever to help you remember
Click the IPV4 tab
Method: Shared to other computers.
By default it does NAT, not bridging, so your connected computer will get a 10.x.x.x address, not a 192.168.x.x.
It beats setting up a dd-wrt as an ethernet bridge by a small margin. However, that doesn't look too difficult either. I just didn't have the time to fiddle with it.
Ubuntu Internet Connection Sharing
By AJ ONeal
Thanks! It's really motivating to know that people like you are benefiting from what I'm doing and want more of it. :)
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