My Ubuntu machine's IP and MAC addresses show up in the DHCP Clients Table in my Linksys router/switch's admin utility, but its Client Hostname cell is empty. All my Windows machines display their ...

This isn't a new problem, but it's driving me nuts since Mojave seems to have made it worse. I have a number of Macs (and other Apple devices, including an Apple TV) and all of them have now started ...