I recently installed Ventura on two drives on my 2018 Mac Mini. After doing so, the internet connection was toast.
I tried WiFi, Ethernet, and Ethernet via a USB-C hub. The Ethernet cable is good: it works fine connected to a different Mac, and fine on this Mini if I’m not booted from Ventura.
On WiFi, neither the 5G nor the 2.4 channel could maintain a connection. On both Ethernet and WiFi, I could see the Dropbox icon in the menubar go from on to off about every two seconds. When I launched Evernote, at the same intervals I see “connected” and then “not connected” notifications in a seemingly endless cycle.
I couldn’t find anything in the network settings that would address this repeated on-off symptom. When I booted the Mini from a Catalina drive, the network options worked perfectly.
Eventually I wiped the drives, installed Monterey, and internet access was back to normal. I’ve never seen this problem before: it was as if there was a switch that a gremlin was flipping on and off in an endless cycle. I have Ventura on two M1 Macs, and have seen no such issues.
I am running macOS Ventura on a 2017 Mac. The 2018 Intel Mac Mini appears to have recurring network driver conflicts with Ventura, particularly when using USB-C hubs or peripherals: some USB hubs can interfere with WiFi/Ethernet connectivity.
In the first link below the OP writes that the issues resolved but he’s not sure how: “I have deleted the “Wifi” entry in the parameter > network setting. Then I have recreated it, it may have helped, but I can’t be sure.” The 2nd person said using USB3 ports wreaked havoc.
But these links are old and macOS Ventura has been periodically updated since then so I can’t say how valid the comments are today.
I uncovered some of that while searching for problem reports. I had a USB3 (A) hub connected — swapping it for a different one made no difference. Switching to a USB-C hub also made no difference. It seems like it has to be a Ventura problem specific to that model. I should have just left the Mini as it was, with a Big Sur install on the internal drive that worked just fine, especially since Big Sur worked with a couple of interface enhancements that I like (cDock, Boot Buddy). Someday when I feel brave, I’ll add a guinea pig drive and install Sonoma on it.