No Internet via LAN

I own a NETGEAR Orbi Pro AC3000 Business Mesh WiFi System, 2-Pack, Wireless Access Point (SRK60) and cannot access the internet via ethernet hard-wired LAN. I have a multitude of wireless devices that can access the internet just fine via the Orbi. My desktop computer is a MAC Pro running High Sierra 10.13.6, and I also have a MacBook Pro running the same person of High Sierra. These computers can connect to the internet using WiFi, but if WiFi is turned off, then there is no internet available via LAN.

 

Devices that are hardwired to the LAN are able to communicate with each other (for example, one can access shared disks across the LAN, or can print to the LAN printer). But I am totally at a loss as to why I suddenly cannot simply use my LAN without WiFi to connect to the internet through the Orbi Pro.

 

My LAN card does not have any hard-coded DNS, or Search Domains.  TCP/IP IPv4 is configured with a fixed manual address using DHCP.

The Orbi Satellite has nothing connected to any of its Ethernet ports.  The Router firmware version is V2.2.1.210.

 

I welcome any suggestions.