Eero and PPPoE
I have a DSL provider here in the great state of Idaho called Century Link. They provide me a 1000Mbps download and 1000Mbps Upload (well not always). Their system is not capable of a normal Bridge Mode. To complete bridge I have to set the Gateway to DMZ Hosting. However the router used has to be able to then connect to the ISP via login credentials provided. Unfortunately I Eero does not support PPPoE credentials.
I can either run the Eero and Gateway in Double NAT, turning off the Wireless Radio or Run the Eero in Bridge mode, but lose a lot of its capabilities. I currently have it running in Bridge Mode.
With that said, each and every iOS and macOS device connected wirelessly without fail each day will show connected to WiFi, but the connection doesn't receive or send data. I am constantly turning off the WiFI or going to Airplane mode briefly. This almost has me at my wits end with the Eero Devices.
Further, In an earlier Mac Geek Gab talking about this subject it was mentioned that if you put the Gateway and Eero in Double NAT then put the Gateway in DMZ mode the Gateway will go into brides mode. I am not sure of this, but have attached a picture to show what that setting looks like in the router.
My question is two fold, first what can I do to get rid of the annoying loss of WiFi on all devices daily. Second Can I really put the Router in DMZ after establishing a Double NAT and have it work.
For the Eero issue my last option I haven't tried is just factory restoring the Eero and starting over from scratch. Leave it in a Double NAT and live life hoping for the best.
Also a TP Link Switch is involved in the connection from the Gateway to the Eero. The Gateway goes to first Eero. Eero goes to switch, switch sends signal to 7 ethernet ports in the home where other two Eero's connect via ethernet and then broadcast. The other 5 ports are used to connect to 3 Apple TV devices directly, 1 to my Drobo 5N and 1 is not used currently. Could I have a bad switch, bad ethernet cable?
The DMZ question if completing what I think was stated, has me way too cautious.
This past weekend I installed a new switch and Ethernet Cable running from the Eero to the Switch. All has performed as planned with the Eero for the past few days. I will keep you posted if I experience any further issues.
Sounds like @PaulK got you sorted with Transparent Bridging, that seems like the best choice given your options.
For anyone else here, though, it's important to note that setting DMZ doesn't actually do anything to put a device in bridge mode. It kinda/sorta emulates it, but that's about as far as it'll go.
As for your issue with your devices losing their ability to talk to/from the Internet, I recommend contacting eero support. They have the ability (with your permission) to see pretty deep into your network, and might well be able to help.