having fun

История IP

Весьма занятное, я бы даже сказал — фундаментальное чтиво (The world in which IPv6 was a good design): https://apenwarr.ca/log/20170810 (pdf)

Anyway, I digress. The salient detail here is that unlike real IP services, bootp and DHCP need to know about ethernet addresses, because after all, it’s their job to hear your ethernet address and assign you an IP address to go with it. They’re basically the reverse of ARP, except we can’t say that, because there’s a protocol called RARP that is literally the reverse of ARP. Actually, RARP worked quite fine and did the same thing as bootp and DHCP while being much simpler, but we don’t talk about that.

И небольшое ревью спустя три года, не менее фундаментальное, чем предыдущая статья (IPv4, IPv6, and a sudden change in attitude): https://apenwarr.ca/log/20200708 (pdf)

И немного рекламы после ревью: Tailscale+WireGuard. Авторы в этих сервисах видят решение основной нерешённой проблемы ipv6 — коннективити при смене ip-адреса:

IP mobility is what we do, in a small way, with Tailscale’s WireGuard connections. We try all your Internet links, IPv4 and IPv6, UDP and TCP, relayed and peer-to-peer. We made mobile IP a real thing, if only on your private network for now. And what do you know, the math works. Tailscale’s use of WireGuard with two networks is more reliable than with one network.

Also: hilbert map of IPv4 address space, same for IPv6

3d-printed parts annealing

https://blog.prusaprinters.org/how-to-improve-your-3d-prints-with-annealing_31088/ (pdf)

Long story short:

Sadly, we found out that the level of warping makes both materials completely unusable for such parts with complicated shapes and relatively precise dimensions

What is annealing good for, then? It does its job with simple parts, which need to improve their mechanical durability and tensile strength. As an example, we annealed simple hooks, which could use some more tensile strength. We printed them from PLA and annealed at 90 °C (194 °F) for 30 minutes. Another example is two PETG prints: a cupboard handle and a simple measuring cup, again, annealed at 110 °C (230 °F) for 30 minutes.

Some ways for organizing linux desktops/workflows/terminals

Прекрасная статья-обзор организации процесса в текстовых терминалах в терминальной стадии: http://jacobzelko.com/workflow/ (pdf)

Таскбар в screen делается записью в ~/.screenrc, что-то типа:
hardstatus alwayslastline "%{bw}[%H] [%?%-Lw%?%{wb}%n*%f %t%{bw}%?%+Lw%?]%=%{bw} [%1`] [%c:%s] [%l]"

Недавно узнал, что window-менеджеров не десять штук, а в разы больше =) Например, HiveOS использует легковесный аскетичный Openbox WM + Tint2: