Issues with XB8 Gateway Connecting a Switch

I have had an XB6 Gateway for 7 years, I have a 1 gb switch connected to the back ethernet port for devices that are wired only. It has worked fine for 7 years. I upgraded to the XB8, went through the xfinity app to set it up and wifi was up an running, plugged in my switch and nothing on the switch works, the data lights from the port to the gateway are not lighting up on either the gateway or switch. If I plug any of the items into the gateway independent of the switch, they work fine. I went back to the XB6 and plugged the switch back in, all works fine. Why won't the XB8 work with a switch? How else would anyone plug items into the gateway that are hardwired only...you have to use a switch.