Meetups/Infra/2026-01-19

Networking, post-mortems, CNAMEs, and spaaaaace.

Topics today

• networking -- NAT hole punching
• post-mortems
  • cloudflare -- DNS CNAME --
  • cloudflare --
  • brixo.com -- ai observability, like with SWE, but for chatbot conversations, perhaps mcp monitoring

• aerospace computing, for satellites (and [data centers in space])

• quick restarts for agentic development that .. (mangages VPS?).

Introductions

• [name] - [background]. [goals for meetup, or interests to explore]

• Loren - does freelance dev work, wants to explore post mortems
• Bryce - software engineer, tentacles into devops
• David - adhai-pal (sp) startup teaching kids language in india
• Derek - dev, learning enough to not lose my job to ai
• Zacky - hacking integer iterpolating floating point with integers (to make ai better so he doesn't have a job anymore)
• Doug - Engineering economist, likes computers a lot.
• MrName(Kevin) - likes computers, dovetailing with post mortems, brixio.com, AI observability, more about chat bot conversation evolving into MCP conversations, improving quality of results they have blog about how spoil an entire clients relationship by having shitty chat bot and monitoring sidesways it goes.
• Chris - run an aerospace company, starup computers for satellites in rockets, technology is inevitible, data centers in space.
• Riley - moved here last week, house doesn't have a bed yet. Work at a startup trying to replace my job, self-hosting, with AI. Talk to me about type theory & language stuff.
• Gwen - life long learner
• Matty - home server at home, hasn't run it in awhile.
• Elan - distinguishes himself: hates learning, has never learned a thing in his life, is a luddite. Interested in self hosting, private authoritative DNS and private CDNs.

• Tatiana - physicist, working in startup, with ...ai? to detect weapons

Lesson or Demo

• Read aloud: clarify for meetup. We are taking notes in a riseup pad (or I am--help appreciated, and links). We have meeting notes posted to the wiki. noisebridge.net, search Infra, or Meetups/Infra. (the Infrastructure page has a disambiguation link.)
• Shell, web services, self-hosting, networking!

Nat hole punching: ip4 didn't have big enough space, so we have routers that provide a private address space. Run a service on your laptop, in theory we could forward traffic to it, but too complicated for brief services. For self hosting, setup a VPN to let people make connection to the LAN.

Do subnets come into play for handling requestion from outside the LAN. Subnet masks separate hosts and network part of address.

CIDR routing IP/24, IP/8.

• Cloudflare Timeout Issue: https://community.cloudflare.com/t/cloudflare-time-out-issue/590317

• https://blog.cloudflare.com/cname-a-record-order-dns-standards/

Cloudflare, our leader in yolo. (and properly undoing it).

According to close reading of the spec, cloudflare was correct. The post mortem found that the ANSWER section was out of order resulted in failure in domain resolution.

Noisebridge DNS: https://github.com/noisebridge/infrastructure/blob/02764bad2625ad349d781e3c74ef3223aa07d38a/files/coredns/zones/noisebridge.net

https://github.com/noisebridge/infrastructure/blob/02764bad2625ad349d781e3c74ef3223aa07d38a/files/coredns/zones/noisebridge.net

Wireshark for MCP  !! topic for another week

reliability in space, post-mortems, & data centers

Loren -- hoping for post-mortems, engineering fault analysis, and data centers in space

Engineering fault analysis is essentially no longer done.

Chris Aerospace. Uses hardware that's known to work. modern consumer hardware is used with smaller area results in fewer events.

[mathematical] models have been developed for predicting how orientation affects particle event (bitflips)

scattering -- shielding can cause 1 high energy particle to become many lower energy particles, which are still high-energy enough to cause errors, but now more numerous.

FPGA?

https://betrusted.io/

Questions

• What many alternative approaches to "no fail hardware" could be considered? What do you prefer / think is best?
  • redundancy is one approach. Often chosen now. Failure possibilities multiply.

Outro

• Doug - liked learning about space -- fulfilled my objective about always be learning
• Peter - space++
• Elan - reinforced my understanding of the importance of ordering, and that people may come to rely on it
• Bryce - will go learn about different kinds of DNS recovered
• David - handling faults in chip differ
• Derek - masking, responsible for splitting out the masking, net mask, is responsible for defining the IP (network versus host) portion of the address.
• Zacky - Got zoned out working on compilers
• Robert - /proc filesystem, special files that contain files about processes on linux
• Kevin - was teaching robert about this
• Chris - Learned that people are interested in hardware/systems reliability in space,
• Matty - not what a CNAME record is, but how it works, how DNS resolution happens
• Riley - reading things with people is fun. Reading the CF/dns/cname post with people, I learned more. VMs, definitions, semantics,
• Loren - space stuff .. topics for the future excited about rotating topic schedule, about the theme for each week, allow more topics of interest relevent to everyone.
• Elan - post meetup topic (already outro'd) -- self-hosting for internal

hedgedoc, CCC hacker conference in hamburg, lots of

https://media.ccc.de/

new talks still being added.

Hosted Noisebridge Zulip instance! https://noisebridge.zulipchat.com/join/4ljvlhqoy7j5ixxamkcsnjsu/

Questions, Discussion, or Coworking

• [Issue]

For next time

Readings & Exercises

• Readings
• Exercises

Join online

• Try it yourself!
  • Join libera.chat #nb-meetup-infra

https://www.noisebridge.net/wiki/Meetups/Infra