Or perhaps electronic devices are really variable in their response to surges. Anyway, last week we had a thunderstorm with a lightning strike close enough that the roof rattled, and the internet went out. Power didn’t even blip, but no more connection to the outside world. Even though those bits come into the house via optical fiber.

I went down to the basement and started checking. Rebooted the little fiber interface box. Our router (which is an old pc running pfsense) rebooted as well as it ever does, but the LAN interface wouldn’t come up. Router front page was quite clear that we had a connection to the outside world, but the router had nowhere to pass it on. And by golly when I looked at the network card the little blinkenlight next to that RJ-45 socket wasn’t lit. Replacing the ethernet patch cable with a spare did nothing useful. (And of course in the basement with no internet searching for possible solutions was not happening.)

The old PC’s motherboard also has an ethernet plug, so I tried that. The little light went on, and after a couple of tries I convinced pfsense to reassign its LAN connection there. Hurrah! Internet! I rushed over to the ancient mac in the corner of the basement to search for more stuff to do, and nuh-uh. The ethernet switch over there that talks to the mac, my daughter’s server farm, and the 3D printer had only one light lit, next to the first ethernet port, and it didn’t matter whether anything else was plugged in or not.

Also, back by the router, the little dongle that does our phone connection was hot to the touch, and no phone service was coming out of it, regardless of how many times I power cycled. So I went upstairs where we have mobile service and called our fiber people (and they said they might have a tech out in a couple weeks). That’s where we’ve been.

Until yesterday, when a replacement ethernet switch arrived for the mac/printer/farm corner, and I plugged that in. Everything lit up fine, and the mac was happily pinging the router (200 microseconds) and chattering with the outside world. But the raspberry pi that controlled the printer, No ethernet light, no lights anywhere. It’s powered in a little bit of an unorthodox way (from the printer power supply through the 5V and Ground pins on the GPIO), so just to make sure I took it upstairs and plugged USB power into it. Doornail. Luckily I have some spares (maybe even a faster one), so that will be replaced soon too.

Let’s recap: the lightning killed the LAN port on the router, but not the WAN port even though they’re one the same board. It killed the IP phone dongle, but left the main ethernet switches between the dongle and the router untouched. Killed the subsidiary ethernet switch in the corner, and the attached raspberry pi, but left the attached mac untouched. Didn’t touch the house’s electrical power. So I’m trying to figure out how the EMP got into the network (remember that ethernet cable is shielded) and how it killed the particular things it did while leaving others untouched. Maybe through the house’s internal telephone wires, which aren’t shielded? But then…

Lightning is weird.