The Gray Node

Foreword Cutting costs has always been and remains to be one of the hot topics in all sorts of businesses and as engineers, we tend to feel constrained or limited by it.

What We Will Learn In this article, we will learn how to: Generate random syslog messages using the logger utility Modify packet captures using Tcprewrite Replay packets (pcap/pcapng files) in a controlled way and locally using Tcpreplay with the help of…

The following post is about a challenge that we encountered at work while extending an in-house-built program that provides automation for 14,000 network devices in our infrastructure.

Introduction In this post, we will learn about a useful tool called the bpftool which is a command-line utility in Linux for interacting with eBPF programs and maps.

Introduction In this post, we will learn about portable or relocatable eBPF programs.

Introduction In this post we will write the user space part of our eBPF program, flat to calculate and display the network latency using the data we gather in the kernel space program.

Introduction In this post we will pick up where we left off and write the backend or kernel space eBPF code for our program, flat to monitor the network latency in a very efficient way.

Network Headers While writing the part two of Building an Efficient Network Flow Monitoring Tool with eBPF, I felt the need to visualize and lay out a foundation on how packet headers are defined in the Linux kernel to make it easier to grasp the concepts…

Introduction In this post we will learn about the big picture and how to structure our eBPF program named flat to monitor network latency.

Introduction In the previous post, I wrote about what eBPF is and the network latency tool that we are going to write.

My Journey This section is about my background.

Overview Environment variables are a simple and popular option to avoid hard-coding credentials into your code or build files, while eliminating the risk of accidentally pushing sensitive information to Git.

Overview Since ChatGPT’s release back in November 2022, I have been playing with it for various subjects, from network infrastructure questions, programming and all the way to conflict management.

A Bit of a Backstory During the many years that I have been privileged working at many different companies and through those, with other ones, I would say the most critical one was a multi-data center company that was handling millions of requests per day…

If you have ever wondered what paths packets take to traverse networks, chances are that you have used or heard of traceroute. traceroute or some variant of it is available on almost all operating systems.

Here are some of my projects that I have been able to open-source or contribute to in no particular order.

Why Do You Need Different Python Versions?

What is TCPDUMP?