Before having HA up and running, I have been using a NOVA mesh system for coverage, one or two routers alone would not suffice. Problem: I hope to use HA to allow operation of smart devices, cameras, and more even when our internet connection is not working well; however, when the internet connection is sufficiently poor, the mesh system stops functioning even if HA is still running. (HA hub connected to the mesh system by ethernet cable.) So even if HA were able to function as intended, it is cut off from all devices until the internet is sufficiently functional and the mesh system returns to proper operating status.
You will only have issues when it comes to internet reliant integrations. If you build your setup around devices that use the local only wifi, zigbee, z-wave and matter+thread protocols you are less reliant on the cloud services in majority of cases.
If the mesh system as a whole degrades when there are internet issues then you need to look into a more independent system.
I use an Asus RT-AX88U as my primary node in my setup which is hosting my internet connection and its connected to an Asus RT-AX92U mesh node that is converting my wired camera into a wireless one via the 5GHz backhaul connection.
My current network and setup has no issues working even if the internet goes under maintenance as the only function I loose at that time would be to remote in via VPN to control and manage devices when not at home (I may invest in a failover 5G connection when I can afford it if I really need it at the time).
I only have a few internet reliant integrations (weather, electricity maps, tuya, IFTTT, vesync and world air quality index) at this time but those are not critical to the function of my main automations and control as I have all my devices currently on local only wifi, zigbee and a few via matter that are used daily.
Many of the WiFi mesh networks use cloud AI to manage the APs in the mesh and that fails with a poor internet connection.
If you can not improve your internet connection, then use local WiFi controller and the supported APs for that.
It might mean you have to replace your entire WiFi and local WiFi controllers are not cheap, because they have to be quite powerful to adjust APs in near real time.
I use a Cisco WLAN controller myself and I think Ubiquiti Dream Machine works like one too, but I have not worked with Ubiquiti Dream Machine myself.
No issues operating disconnected from the Internet.
Op - if your mesh gear doesn’t work disconnected from the Internet or in periods of poor internet connectivity. It’s probably not the right gear for your use case. That’s your issue.
I appreciate the information! The internet here is good most of the time, but there are exceptions that bring me to this issue.
If the mesh relies on the internet to manage itself and connections with devices, and there’s no way to provide that management locally, then It could be I’ll need to go another direction, or just put up with the occasional downtime.
I would take the hardware and bring it back where it came from. If your network gear isn’t capable of providing simple LAN (including WiFi mesh) without WAN connection it is simply trash.
Next time get yourself hardware that is capable of running openwrt so you are not forced into the walled garden of the vendor
For those who have been critical of my current mesh system: while your criticism may have some valid points, I did note in my OP that my mesh system preceded my adoption of HA and I had no need to consider controller capabilities prior to adopting HA.
I am now researching specific equipment that would provide needed capabilities at lower (not necessarily absolutely the lowest) cost. If you have specific suggestions (brand, model number, why that choice) suitable for a residence with a few hundred devices maximum, that would be helpful.