Notes

How to reconcile logical clocks with wall clocks? Two algorithms: Lamport. Total order, consistent with causality. Vector clocks. Related but not same as version vectors. Q: how to merge two event timestamps? Q: how to compare? How to find incomparable? Timestamps summarize everything that happened before. Partial vs total order: Partial == happens before: order only between causal events, none between concurrent. Basically, some events are incomparable. Total: order defined for each pair of events. Timestamps are incremented before message sent to another node and when received.

Good mobile apps for iPhone that support VoIP: Bria Mobile. Zoiper.

Michael’s Bellevue: Bickford: Airport: Good pricing. Clearview: $730 or so, July 27. Kirshner: $900 for August 2. Truck builders: Don’t do. U-haul phone number: 800-468-4285

This website describes color coding of wires, why you need a neutral wire and how to find it. I’ll most likely have neutral wires in our wall switches. However, it seems neutral is NOT mandatory in the switch - if the switch doesn’t require neutral, that should be okay.

Here are some good water leak detectors I found in my research: Shelly: About $29 per device: https://www.shelly.cloud/en-us/products/shop/shelly-flood/4xflood-us Govee: One way: 3 sensors + hub is for $45: https://www.amazon.com/Detector-Wireless-Notification-Security-Basement/dp/B07J9HZ5VN 2 more sensors (if we need) is for $23 more: https://www.amazon.com/Govee-Wireless-Detector-Basement-Apartment-dp-B07JB84351/dp/B07V4R16HX So, total $68 for 5 sensors and a hub. Another: 5 sensors for $42: https://www.amazon.com/Govee-Detectors-Wireless-Detector-Sensitive/dp/B07QSFRSJX 1 sensor + hub: $13: https://www.amazon.com/Govee-Wireless-Detector-Basement-Apartment-dp-B07JB84351/dp/B07V4R16HX So, $55 for 6 sensors and a hub. Or $65 for 7 sensors and a hub. One potential problem is that the hub may not cover the entire house. Says 100m but the number would be less when there are walls and floors in between.

Shelly 1 (not the “Plus” model) needs to be powered separately from the garage. 12V DC supply probably best. Need to change jumper position. There is a connector that I could use to reuse electricity supply from garage. Or provide another source which could be a 12V DC supply. Sending a command to the garage motor should be simple - just need to hook up 2 wires from Shelly to it.

One of the best parts of my current trip to Europe was that I got quality and loads of dedicated time with my kiddo. In our day to day lives when we aren’t traveling, that rarely happens because of our and, primarily, the kiddo’s busy schedule - the most we get is a 3-day long weekend once in awhile. So, this 20 day trip brought a welcome change.

The train system and both cities we’ve visited so far, Lausanne and Interlaken, have been crazy expensive. (It wasn’t so expensive even in a major city like Paris.) I regularly sense racism here. For example, people aren’t friendly and I speculate the reason is the color of my skin. I find this strange given how much revenue the country must be earning from Asian tourists such as myself. That’s another thing: the tourist crowd is predominantly Asians, possibly because they have the money to spend on tourism in such an expensive country. So, on the contrary, racism should be lower. The train+gondola ride to Jungfraujoch was amazing. I am marveled by human engineering that must have first created this a century ago. On top of that, the facilities were so nice. Sparkling clean bathrooms, stroller friendliness, heated indoors, restaurants and shopping etc.

Note: Next version here. If we visit a single country at a time, it becomes easier to optimize for and understand the public transportation situation. A 10 day trip plus ~2 days of travel sounds like a good idea. Train tickets: The official website to book train tickets is SNCF Connect in France and SBB in Switzerland. Another one, likely a travel agency, is Rail Europe. In at least one case, we found cheaper tickets here compared to SNCF. EU Rail passes can also be a good option. Tickets can be pretty expensive closer to travel time. Book at least 1-2 days earlier. Book hotels and apply for visas, both as early as possible. Helps getting good prices. It’s often cheaper to book directly with a hotel compared to going through websites like booking.com. This time, I didn’t plan much before arriving here and that wasn’t a great idea. I should’ve briefly checked online what activities are available in every city we visit, so that we could book the more popular once earlier. Search for 1, 3 etc. day (travel) passes. Can be cheaper sometimes. Also, check for country specific train or travel passes. Can be cheaper. Pack light: it helps a lot. Don’t cheap out on cellular data as it gets used up quickly. Google Maps eats a lot, so download offline maps through wifi. (For e.g., 6 GB is barely sufficient for a 20 day trip, assuming there is wifi in hotels.)

After self-hosting Mail-in-a-Box for a few months, I ended my experiment and moved to Migadu so as to let more experienced folks manage this critical infrastructure for me. As part of that migration, I learnt that MIAB sets up an MTA-STS policy and Migadu, by default, doesn’t guide you to do that. That led to Gmail failing to send emails to me because it was caching the older but no longer valid policy. ...