It’s been a quiet Christmas for my weather watching and on the forum. I’ve been busy with other things. Santa brought me a major LAN upgrade to install and whilst it’s been tricky I think I’ve now got it all working.
I now have a dedicated OPNSense firewall protecting the LAN and acting as the main house router. The ‘old’ WiFi router (which is still a very good WiFi device) is now acting as a WiFi Access Point. I also have Power Line Adapters providing wired Ethernet points and additional WiFi Access Points to more locations in the house. PLA technology has really come on in recent years. The link from my ‘office’ back to the Internet connection is running at 1.3Gbps…across mains wiring!
I was worried about the migration. I needed to shut the existing LAN down whilst I put the new router in and that’s not easy when the Smart House is using that LAN to control things. In the end the control side of things went pretty well, but the smart controller (Home Assistant on a Raspberry Pi) lost its connection to the outside world. I spent a couple of days puzzling over why that was happening. The (two different) firewalls didn’t seem to be blocking it, but given that both are new to me it took much longer than it would normally do to check that.
In the end it was an ARP problem. If you don’t know what ARP is, don’t worry. If you do know what it is, then you might understand why me setting my DHCP reservations to have a static ARP wasn’t a good thing. Devices got confused about who they really were 
I think I’m over the worst now, so I can now start to learn how to better manage my new router/firewall, and get back to looking at some weather data. I think it’s been raining?
