Explore your Cloudflare data with Python notebooks, powered by marimo

Many developers, data scientists, and researchers do much of their work in Python notebooks: they’ve been the de facto standard for data science and sharing for well over a decade. Notebooks are popular because they make it easy to code, explore data, prototype ideas, and share results. We use them heavily at Cloudflare, and we’re seeing more and more developers use notebooks to work with data – from analyzing trends in HTTP traffic, querying Workers Analytics Engine through to querying their own Iceberg tables stored in R2.

Traditional notebooks are incredibly powerful — but they were not built with collaboration, reproducibility, or deployment as data apps in mind. As usage grows across teams and workflows, these limitations face the reality of work at scale.

marimo reimagines the notebook experience with these challenges in mind. It’s an open-source reactive Python notebook that’s built to be reproducible, easy to track in Git, executable as a standalone script, and deployable. We have partnered with the marimo team to bring this streamlined, production-friendly experience to Cloudflare developers. Spend less time wrestling with tools and more time exploring your data.

Today, we’re excited to announce three things:

• Cloudflare auth built into marimo notebooks – Sign Continue reading

Demystifying Ultra Ethernet

The Ultra Ethernet Consortium (UEC), of which Arista is a founding member, is a standards organisation established to enhance Ethernet for the demanding requirements of Artificial Intelligence (AI) and High-Performance Computing (HPC). Over 100 member companies and 1000 participants have collaborated to evolve Ethernet, leading to the recent publication of its 1.0 specification, which will drive hardware implementations that significantly boost cluster performance.

The Art Of The GPU Deal

Perhaps the most interesting conversation that has happened so far in the White House in 2025, at least from the point of view of the IT sector, is when Nvidia co-founder and chief executive officer, Jensen Huang, put on his Sunday best suit and visited President Donald Trump to presumably talk about technology, AI, trade, and war on July 10. …

The Art Of The GPU Deal was written by Timothy Prickett Morgan at The Next Platform.

Cloudflare 1.1.1.1 incident on July 14, 2025

On 14 July 2025, Cloudflare made a change to our service topologies that caused an outage for 1.1.1.1 on the edge, resulting in downtime for 62 minutes for customers using the 1.1.1.1 public DNS Resolver as well as intermittent degradation of service for Gateway DNS.

Cloudflare's 1.1.1.1 Resolver service became unavailable to the Internet starting at 21:52 UTC and ending at 22:54 UTC. The majority of 1.1.1.1 users globally were affected. For many users, not being able to resolve names using the 1.1.1.1 Resolver meant that basically all Internet services were unavailable. This outage can be observed on Cloudflare Radar.

The outage occurred because of a misconfiguration of legacy systems used to maintain the infrastructure that advertises Cloudflare’s IP addresses to the Internet.

This was a global outage. During the outage, Cloudflare's 1.1.1.1 Resolver was unavailable worldwide.

We’re very sorry for this outage. The root cause was an internal configuration error and not the result of an attack or a BGP hijack. In this blog, we’re going to talk about what the failure was, why it occurred, and what we’re doing to Continue reading

Cloudflare recognized as a Visionary in 2025 Gartner® Magic Quadrant™ for SASE Platforms

We are thrilled to announce that Cloudflare has been named a Visionary in the 2025 Gartner® Magic Quadrant™ for Secure Access Service Edge (SASE) Platforms¹ report. We view this evaluation as a significant recognition of our strategy to help connect and secure workspace security and coffee shop networking through our unique connectivity cloud approach. You can read more about our position in the report here.

Since launching Cloudflare One, our SASE platform, we have delivered hundreds of features and capabilities from our lightweight branch connector and intuitive native Data Loss Prevention (DLP) service to our new secure infrastructure access tools. By operating the world’s most powerful, programmable network we’ve built an incredible foundation to deliver a comprehensive SASE platform. 

Today, we operate the world's most expansive SASE network in order to deliver connectivity and security close to where users and applications are, anywhere in the world. We’ve developed our services from the ground up to be fully integrated and run on every server across our network, delivering a unified experience to our customers. And we enable these services with a unified control plane, enabling end-to-end visibility and control anywhere in the world. Tens of thousands of customers Continue reading

HW056: From Emergency Response to Instant Branch: HiveRadar’s Portable Edge

Dry Run: Your Kubernetes network policies with Calico staged network policies

Kubernetes Network Policies (KNP) are powerful resources that help secure and isolate workloads in a cluster. By defining what traffic is allowed to and from specific pods, KNPs provide the foundation for zero-trust networking and least-privilege access in cloud-native environments.

But there’s a problem: KNPs are risky, and applying them without a clear game plan can be potentially disruptive.

Without deep insight into existing traffic flows, applying a restrictive policy can instantly break connectivity killing live workloads, user sessions, or critical app dependencies. An even scarier scenario is when we implement policies that we think cover everything and workloads actually work, but after a restart or scaling operation we hit new problems. Kubernetes, with all of its features, has no built-in “dry run” mode for policies, and no first-class observability to show what would be blocked or allowed which is the right decision since Kubernetes is an orchestrator not an implementer.

This forces platform teams into a difficult choice, deploy permissive or no policies and weaken security, or Risk service disruption while debugging restrictive ones. As a result, many teams delay implementing network policies entirely only to regret it after a zero-day exploit like Log4Shell, XZ backdoor, or other vulnerabilities Continue reading

PP070: News Roundup – Scattered Spider Bites MSPs, Microsoft Rethinks Kernel Access, North Koreans Seem Good at Their Illicit Jobs

Hyper-volumetric DDoS attacks skyrocket: Cloudflare’s 2025 Q2 DDoS threat report

Welcome to the 22nd edition of the Cloudflare DDoS Threat Report. Published quarterly, this report offers a comprehensive analysis of the evolving threat landscape of Distributed Denial of Service (DDoS) attacks based on data from the Cloudflare network. In this edition, we focus on the second quarter of 2025. To view previous reports, visit www.ddosreport.com.

June was the busiest month for DDoS attacks in 2025 Q2, accounting for nearly 38% of all observed activity. One notable target was an independent Eastern European news outlet protected by Cloudflare, which reported being attacked following its coverage of a local Pride parade during LGBTQ Pride Month.

• DDoS attacks continue to break records. During 2025 Q2, Cloudflare automatically blocked the largest ever reported DDoS attacks, peaking at 7.3 terabits per second (Tbps) and 4.8 billion packets per second (Bpps).

• Overall, in 2025 Q2, hyper-volumetric DDoS attacks skyrocketed. Cloudflare blocked over 6,500 hyper-volumetric DDoS attacks, an average of 71 per day. 

• Although the overall number of DDoS attacks dropped compared to the previous quarter — which saw an unprecedented surge driven by a large-scale campaign targeting Cloudflare’s network and critical Internet infrastructure protected by Cloudflare — the Continue reading

Blog Reboot

When I first launched this site, many years ago, it served as a humble lab notebook and sharing short personal stories from my working life. I shared diagrams, Junos configs , and field notes written after late night maintenance windows or proof of concepts. Those stories took on a life of their own. They brought […]

netlab 25.07: Summaries and Confederations

netlab release 25.07 was published yesterday. The major new features include:

• The ospf.areas plugin supports OSPFv2 and OSPFv3 stub areas, NSSA areas, and area ranges.
• The BGP routing policies plugin supports aggregate BGP routes
• The BGP configuration module supports BGP confederations

But wait, there’s much more:

Integration Testing in Infrahub – Validate Your Automation in Real Environments

Testing individual components is a good start, but what happens when you need to validate how everything works together? In this post, we’ll show you how to run integration tests in Infrahub that verify your schema, data, and Git workflows in a real, running environment.

You’ll learn how to spin up isolated Infrahub instances on the fly using Docker and Testcontainers, automate schema and data loading, and catch issues before they reach production.

You don’t need to be a Python expert to follow along. We’ll walk through everything step by step, with example code and tooling recommendations. You can also follow this guide in video form on the Cisco DevNet YouTube channel:

• Building a Production-Grade Automation Platform With Infrahub – Part 1
• Building a Production-Grade Automation Platform With Infrahub – Part 2

All the sample data and code used here are available on the OpsMill GitHub repo, so you can set up your own test environment and try it yourself.

Quick recap

Previously, we covered how to write smoke and unit tests using the Continue reading

Triggering QUIC

Brazil Lays The Hardware Foundation For Its AI Ambitions

Every major economy that is not the United States or China, which has a disproportionate share of HPC national labs as well as hyperscaler and cloud builder tech titans, wants AI sovereignty a whole lot more than they ever worried about HPC simulation and modeling. …

Brazil Lays The Hardware Foundation For Its AI Ambitions was written by Timothy Prickett Morgan at The Next Platform.

NB534: Arista Late to SD-WAN Party but Ready to Dance; CoreWeave Acquires GPUs, Gigawatts for $9 Billion

Tech Bytes: Build a Reliable DC Network With Nokia Validated Designs (Sponsored)

Go is still not good

Previous posts Why Go is not my favourite language and Go programs are not portable have me critiquing Go for over a decade.

These things about Go are bugging me more and more. Mostly because they’re so unnecessary. The world knew better, and yet Go was created the way it was.

For readers of previous posts you’ll find some things repeated here. Sorry about that.

Error variable scope is forced to be wrong

Here’s an example of the language forcing you to do the wrong thing. It’s very helpful for the reader of code (and code is read more often than it’s written), to minimize the scope of a variable. If by mere syntax you can tell the reader that a variable is just used in these two lines, then that’s a good thing.

Example:

if err := foo(); err != nil {
   return err
}

(enough has been said about this verbose repeated boilerplate that I don’t have to. I also don’t particularly care)

So that’s fine. The reader knows err is here and only here.

But then you encounter this:

bar, err := foo()
if err != nil {
  return err
}
if err =  Continue reading

AWS Transit Gateway Peering Attachments (VIII)

Hi all, welcome back to the AWS networking series. This is actually part 3 of just Transit Gateway. I know some of you might be thinking, why are we still talking about Transit Gateway? But please bear with me. TGW is such an important concept, and it shows up in almost every architecture you come across.

So far, we've covered what a Transit Gateway is, how to create one, how route tables work, and how to manage associations and propagations. We also looked at how to create a VPN and attach it to the TGW, and we went through the process of sharing a TGW with other AWS accounts using AWS Resource Access Manager (RAM). In this post, we'll look at how to peer a Transit Gateway with another TGW, even when they are in different regions. So let's get to it.

If you're completely new to Transit Gateway, I highly recommend checking out the earlier introductory posts listed below.

AWS Transit Gateway Introduction

This complexity (when you have many VPCs) is why, in this post, we will look at AWS Transit Gateway (TGW). A Transit Gateway is an incredibly important networking resource in AWS that solves these scaling challenges.

Continue reading

Tracing network packets with eBPF and pwru

In this article we will use Multipass to create a virtual machine to experiment with pwru. Multipass is a command line tool for running Ubuntu virtual machines on Mac or Windows. Multipass uses the native virtualization capabilities of the host operating system to simplify the creation of virtual machines.

multipass launch --name=ebpf noble
multipass exec ebpf -- sudo apt update
multipass exec ebpf -- sudo apt -y install git clang llvm make libbpf-dev flex bison golang
multipass exec ebpf -- git clone https://github.com/cilium/pwru.git
multipass exec ebpf --working-directory pwru -- make
multipass exec ebpf -- sudo ./pwru/pwru -h

multipass exec ebpf -- sudo ./pwru/pwru port https

multipass exec ebpf -- curl https://sflow-rt.com

SKB                CPU PROCESS          NETNS      MARK/x        IFACE       PROTO  MTU   LEN   TUPLE FUNC
0xffff9fc40335a0e8 0   ~r/bin/curl:8966 4026531840 0               0          Continue reading

Google Brings the Lustre Parallel File System to Its Cloud

Google Cloud now offers a fully managed version of the Google Cloud Managed Lustre service went live (“general availability”) globally on July 8. An open source, high-performance file system, running those supercomputing jobs. And Lustre’s ability to stream data in the range of terabytes per second should also make it appealing to very approximately 1TB) — and can scale up to 8PiB or more. With this release, Google Cloud has caught up with other cloud providers in offering a cloud-based Lustre. It competes with Amazon FSx and Oracle‘s EXAScaler Continue reading