Chapter 1: SONiC Fundamentals

Introduction

SONiC (Software for Open Networking in the Cloud) is a Linux-based open-source network operating system that was originally developed at Microsoft and is now maintained by a broader open-source community. Its core idea is that the same network operating system can run on switch platforms from multiple hardware vendors. This reduces vendor lock-in and provides a more consistent operational model across different environments.

SONiC can also be viewed as an abstraction layer between network operators and the underlying switch hardware. Instead of learning and managing several vendor-specific operating systems, operators can use a common software architecture and management model across different switch platforms. This simplifies network operations, automation, monitoring, and telemetry collection. It can also reduce operational errors caused by configuration differences between platforms and make it easier to onboard new engineers.

Organizations can choose the hardware platform that best meets their technical, operational, and business requirements without being tied to a single software ecosystem. Some vendors provide commercially supported SONiC distributions together with professional support services, while others support community-based deployments or customer-tailored implementations. The appropriate model depends on the organization's operational requirements and support expectations.

From an architectural perspective, SONiC is a modular and container-based system. Major Continue reading

Cloudflare DMARC Management is now generally available

When we first launched DMARC Management, it was driven by a simple belief: every domain on the Internet deserves strong email authentication, and cost should never be the reason it doesn't happen. As part of our mission to help build a better Internet, we made DMARC Management available for free to every Cloudflare customer. We wanted to give everyone the tools to understand and improve their DMARC posture without needing to hire an email security consultant or parse XML report files by hand.

Today, we are taking that commitment further. Cloudflare DMARC Management is now generally available, with a redesigned experience built to help you reach full DMARC enforcement as easily as possible.

^{The DMARC Management dashboard offers a unified view of your email authentication posture.}

Every time someone receives an email "from" your domain, their email provider asks a simple question: did the real owner of this domain actually send this? Without a way to answer that question, anyone can send an email pretending to be you and your recipients will have no way to tell the difference.

Email authentication is the set of DNS records that answers that question. There Continue reading

Building a Soviet Nail Factory: how KPIs killed efficiency

Worth Reading: Leading Intelligent Networks

Chris Grundemann wrote an interesting article arguing that you should structure your network operations around teams, not heroes.

Even if you feel you’re perfectly OK with your network being held together by exhausted heroes (and duct tape), it could be a bit harder to deploy network automation in an always-busy hero culture. However, the choice, as they say, is yours.

DNS Query Duplication

DNS Query Duplication

From Prompt to Exploit: How LLMs Are Changing API Attacks

More Power To You – And To The Datacenters

NB579: Datadog Unleashes Autonomous Agents; SpaceX Launches IPO

Growing the Cloudflare AI team with talent from Ensemble AI

Today, we’re excited to share that key members of the team at Ensemble AI are joining Cloudflare to help accelerate our work in AI infrastructure and make it easier for developers to run powerful AI models efficiently at scale.

Ensemble AI, founded in 2023 in San Francisco, has spent the last few years focused on one of the most important challenges in AI: making large models faster, smaller, and more cost-effective to serve, without sacrificing quality. The team has developed new approaches to model compression and efficient inference that are designed to reduce the memory, compute, and deployment overhead of large language models and multimodal architectures.

As AI becomes a core part of how developers build applications, the economics of inference matter more than ever. Models are getting larger; workloads are becoming more dynamic. And customers increasingly expect AI to be available everywhere: globally distributed, fast, reliable, and affordable. Bringing the Ensemble AI team into Cloudflare strengthens our ability to make that possible.

The team at Ensemble AI has focused on preserving the structure inside modern AI models while reducing the cost of running them. Instead of treating model efficiency as only a quantization or hardware problem, Continue reading

SR-MPLS with OSPFv2

I started my part of the Segment Routing workshop @ ITNOG10 exploring SR-MPLS with IS-IS (simple SR-MPLS, dual-stack SR-MPLS, SR-MPLS over unnumbered IPv4 interfaces). Next step: let’s change the routing protocol to OSPF while using the same network topology:

Thriving Through Volatility: The Everpure Advantage in an Uncertain Market

Quake demos raytraced again

This is a follow-up to a previous post about raytracing Quake demos.

But first, the money shot:

And flat shaded and textured videos. Youtube is Very Aggressive™ with its compression, so the quality there is not good. For pixel quality the above images showcase it better.

A new raytracer

One of my original reasons for creating the quake demo povray files is that it was a good source of data for 3D experiments. POV-Ray is a great raytracer, though entirely CPU (no GPU) and no longer state of the art.

POV-Ray has plenty of built in options, but takes forever to render the 30-60fps demos I want to play with.

Also POV-Ray is AGPL now, so nope nope nope nope nope. That’s a dead end.

Another AI detour

We live in interesting times. We could be living in a time when no two people are running the same email client, or music player, or shell. There used to be a barrier to writing these things custom. I know people who wrote their own shell and use it as a daily driver. I wrote my own email client, and use that.

There are many people out there, me included, who Continue reading

Installing Step CA in My Homelab

Step CA is an open-source private CA made by Smallstep. I will use it to generate certificates for some componenents in my lab.

First we install the dependencies:

sudo apt-get update && sudo apt-get install -y --no-install-recommends curl gpg ca-certificates

Then we get the Smallstep repository signing key:

sudo curl -fsSL https://packages.smallstep.com/keys/apt/repo-signing-key.gpg   -o /etc/apt/keyrings/smallstep.asc

Then we add the Smallstep repository:

cat << 'EOF' | sudo tee /etc/apt/sources.list.d/smallstep.sources > /dev/null
Types: deb
URIs: https://packages.smallstep.com/stable/debian
Suites: debs
Components: main
Signed-By: /etc/apt/keyrings/smallstep.asc
EOF

Then we install step-cli and step-ca:

sudo apt-get update && sudo apt-get -y install step-cli step-ca

Then we check the install:

step-ca version
step version
Smallstep CA/0.30.2 (linux/amd64)
Release Date: 2026-03-23T00:18:00Z
Smallstep CLI/0.30.4 (linux/amd64)
Release Date: 2026-06-10T06:10:28Z

Next, we’ll run the initializer:

step ca init \
  --name "lostintransit.se" \
  --dns "stepca.lostintransit.se" \
  --address ":443" \
  --provisioner "[email protected]"
 Deployment Type: Standalone
Choose a password for your CA keys and first provisioner.
 [leave empty and we'll generate one]: 

Generating root certificate... done!
Generating intermediate certificate... done!

 Root certificate: /home/ddib/.step/certs/root_ca.crt
 Root private key: /home/ddib/.step/secrets/root_ca_key
 Root fingerprint: 8f08102ae41eb7fc6a57f62fbaccaf82cb7a67dbedca858a0352a75b4fa763cd
 Intermediate certificate: /home/ddib/.step/certs/intermediate_ca. Continue reading

AI solving problems

I’ve been able to find some time, lately, to work on my project backlog. And because it’s 2026, I’ve been using AI as a diligent intern.

I’ve ranted before about seccomp, but still used it for a project or two. But then, rarely, it triggered an unexpected openat. That’s exactly the kind of I do want to detect and kill the binary for, so I don’t just want to allow it. I want to know where it’s coming from.

strace showed it’s trying to read /proc/sys/vm/overcommit_memory.

It’s certainly not my code. But just the Rust transitive dependency tree is quite a few crates:

$ cargo tree | sed -r 's/^[^a-z]+//;s/ .*//' | sort -u | wc -l
236

Step 1 was to run it in gdb, and reproduce the problem. But it’s a bit trickier than that, because seccomp fully kills the process, so no backtrace. And setting breakpoints requires a few more syscalls to work, just for the process to work under gdb (e.g. sigaltstack).

And turns out some calls fail with EINTR if running under a debugger.

Yes, I can fix all these things. But why not put the AI intern on it?

AI Continue reading

While Oracle Will Rake In Big Bucks On AI, Profits Are Hard To Predict

Scaling Security Insights: how we achieved a 10x increase in global scanning capacity

Security Insights provides actionable security recommendations for every Cloudflare account. To find these insights, we perform regular scans for all accounts, zones, and DNS records, looking for potential security risks and misconfigurations.

However, two key issues emerged. First, our scans were too infrequent. Scans were only being performed every week or two, and therefore newly introduced security risks could remain undetected for up to two weeks. Second, automatic scanning was opt-in for many free plan accounts – meaning lots of accounts weren’t being scanned at all.

The risks of infrequent or nonexistent scans are rising: as automated attacks accelerate, the window for detecting security misconfigurations is shrinking. Making sure that we’re finding these issues for all of our customers is crucial to our aim of building a better Internet for everyone.

We calculated that to increase our scanning frequencies and enable automatic scanning for all accounts, we would need to increase our scanning throughput by around 10x on average – from 10 scans per second to 100 per second. But our system was already struggling with its load: millions of events were filling up our backlog waiting to be processed; our API was frequently timing out; our processes were crashing. Continue reading

HN831: The Sum, Not Just the Parts: How and Why to Think Holistically About Your Network

AI in Networking with Andrew Yourtchenko

I always wanted to find someone who is more positive about AI than I am, while having solid “can deliver working stuff at scale” credentials. Andrew Yourtchenko definitely fits the bill. I first met him (online) when he was still an engineer in Cisco TAC, and when we finally met in person, he was busy automating the deployment of Cisco Live networking infrastructure. He was also instrumental in bringing us closer to ubiquitous IPv6 deployment with Happy Eyeballs.

Data Synchronisation