Wow, no love for port 31415? It’s the pi port for crying out loud!
I know, it seems irrational of them doesn’t it?
I will admit to using joke numbers in some of my personal, local networking configurations. Port 42069 is a custom SSH port that my raspberry pi is listening on, and I use 172.16.69.* as the IPv4 subnet for my newly-configured local wireguard VPN. I avoid configuring port 9001 for anything permanent, because I like to use that number for custom webapps I’m currently hacking on listening on localhost.
I run a few different local web services on one of my servers, all running behind a reverse-proxy, and which therefore need to be listening on distinct localhost ports. This sort of thing wouldn’t show up in the OP’s data, since I don’t have the reverse proxy configuration checked into any kind of source control (although that would be a neat project for someday). I’ve deliberately tried to use random four-digit port numbers for these, like 3763 and 8580, with the hope that if I pick them at random something I try to install on that computer in the future is unlikely to also want to listen on that localhost port.
I use port 9001 for local development as well.
I’m guilty of using 1337 and 31337. After reading your post, I’ll be adding 42069 to my list.
Instead of a heatmap, which is difficult to navigate, I would prefer the list of all ports sorted by frequency.
There seems to be a frequency list in the linked visualization: https://observablehq.com/@rolandcrosby/ports
I frequently use portnumbers that map a name to digits, as if they were rung in on a phone. E.g., ZOPE would use port 9673, IPFS would use port 4737, et cetera.
Very interesting! Made me dive into my own port usage habits, and here’s what I pulled up.
On the web services I run and then reverse proxy with caddy, I noticed that my lowest port number was 8080 and then each new service I added with time used an incrementally higher one, so 8081, 8082 and so on. Why I started on 8080 is probably explained by how most documentation for docker/docker-compose deployments seem to prefer it.
Back when I used to choose custom port numbers, for things like Shoutcast servers, I would choose them based on the mapping of letters to numbers on a phone keypad, using 4 or 5 appropriate letters.