Archive

Category Archives for "AboutNetworks.net"

Cisco Live 2024 – an Englishman in Vegas

Once again this year, Cisco Live US 2024 will take place in Las Vegas, Nevada, from June 2 to 6, 2024. I’m already registered and I’m looking forward to it! This year will be my 11th time attending Cisco’s annual conference in person, in both Europe and the United States.   Straight to the point I’ve already written a few posts in previous years about what’s interesting to see and do at Cisco Live, and whether the conference is worth attending in person (and of course, it’s worth it!). This…

The post Cisco Live 2024 – an Englishman in Vegas appeared first on AboutNetworks.net.

The Future of Network Engineering in the AI/ML era

It seems like yesterday when I saw my first network automation presentation at a conference. I remember it very well; it was in 2015 at the Cisco Network Innovation Summit in Prague. Mr. Tim Szigeti was presenting the first version of the Cisco APIC-EM, the future Cisco Digital Network Architecture (DNA) controller. I talked already about it in a previous article, written in 2018, about my journey toward network programmability and automation. After its presentation, and for many years afterward, the question was on everyone’s lips: Is this the end…

The post The Future of Network Engineering in the AI/ML era appeared first on AboutNetworks.net.

Cisco Live 2023 – Is the conference worth the price?

Cisco Live US 2023

Cisco Live US 2023 will take place from June 04 to 08 in Las Vegas. I have just registered, and this will be my 10th time attending. However, the question arises: is the Cisco Live conference worth the price? Travel and Accommodation I will not consider the cost of travel and accommodation in this post. This introduces too many variables depending on where the conference is, where you are coming from, and what your preferences are for accommodations. We’re only going to talk about the cost and benefits of attending…

The post Cisco Live 2023 – Is the conference worth the price? appeared first on AboutNetworks.net.

Migrating Cisco FabricPath and Classic Ethernet Environments to VXLAN BGP/EVPN over a 400Gb-based Clos Topology, part 1 – the why

During the past three years, I have spent a good portion of my time testing, planning, designing, and then migrating our DC network from Cisco FabricPath and Classic Ethernet environments to VXLAN BGP/EVPN. And simultaneously, from a hierarchical classic two-tier architecture to a more modern Clos 400Gb-based topology. The migration is not yet 100% completed, but it is well underway. And I have gained significant experience on the subject, so I think it’s time to share my knowledge and experiments with our community. This is my first post on this…

The post Migrating Cisco FabricPath and Classic Ethernet Environments to VXLAN BGP/EVPN over a 400Gb-based Clos Topology, part 1 – the why appeared first on AboutNetworks.net.

SCP not working with MacOS 13 Ventura?

You have updated your MacOS to version 13 (Ventura) and a simple SCP to a network device does not work anymore? In fact, this is normal, here is the reason and how to solve this. The symptom The SCP command that you have already done thousands of times to upload or download a file from/to a network device gives an error, for example: ~ scp nxos64-cs.10.2.4.M.bin admin@myswitch:bootflash:/// (admin@myswitch) Password: subsystem request failed on channel 0 scp: Connection closed   The reason The SCP protocol has been deprecated in OpenSSH 9.0 which…

The post SCP not working with MacOS 13 Ventura? appeared first on AboutNetworks.net.

RobotFramework Debug Logs

This is a very short post, as a complement to my previous post about PyATS, Genie, and RobotFramework.   How to see the debug logs of RobotFramework? I’m doing a lot of testing with RobotFramework and Genie right now. And I had a little trouble getting the right level of debugging to fix my mistakes. Here is a short and efficient way to generate a log file with RobotFramework: Just add the options -L trace and –b your_debug_file.log to have everything you need. For example: robot -d ./output -L trace…

The post RobotFramework Debug Logs appeared first on AboutNetworks.net.

Cisco Live 2022

Cisco Live US 2022 will be June 12-16 in Las Vegas. After two years of virtual conferences and being vaccinated three times against Covid-19, I’m more than motivated to go in person! However, for those who are still hesitating, there is also an online version, over two days, probably in a similar format to 2021. I am really looking forward to it and being able to talk and interact with my former colleagues, friends, and peers again. This is probably the best part about attending a conference in person: meeting…

The post Cisco Live 2022 appeared first on AboutNetworks.net.

Cisco DCAUTO exam study resources

I just passed the Cisco DevNet DCAUTO (300-635) exam (Yay!). This is my 3rd Cisco exam on network automation after NPDESI in 2018 (replaced now by the DevNet program), and DevNet CORE (DEVCOR) in 2020. But this time, I documented everything I read, so I could report it here and build a Cisco DCAUTO exam study resources. By doing this, I hope to help anyone who wants to study for this certification. And, as I have already passed the DevNet CORE exam, I am now Cisco certified DevNet Professional.  …

The post Cisco DCAUTO exam study resources appeared first on AboutNetworks.net.

2021 IT Blog Awards finalist!

IT Blog Awards Finalist 2021

I have the honor of having my blog selected as a finalist in the 2021 IT Blog Awards, hosted by Cisco. It is a privilege and a great joy for me to have my blog selected for the fourth consecutive year! Congratulations also to all of the other finalists, who all produce great and valuable content! Click here to vote and choose the winner of the 2021 IT Blog Awards. If you want to vote for my blog, you can find it under: “Let’s talk about Network“, thank you in advance…

The post 2021 IT Blog Awards finalist! appeared first on AboutNetworks.net.

First steps with pyATS

pyATS

Have you ever wanted to compare the operational state of a bunch of network devices between two specific times? Not only if the interfaces are up or down, but the number and status of BGP peers, the number of prefixes received, the number of entries into a MAC-address table, etc? This is something quite laborious to do with classical NMS or Do-It-Yourself scripts. And this is where pyATS can become a real asset. Here are my first steps with pyATS: Network Test & Automation Solution. What is pyATS? pyATS (pronounced…

The post First steps with pyATS appeared first on AboutNetworks.net.

How to simulate a host in a real network?

How to simulate a host

Like some other posts, I didn’t think I would write this one because it seemed obvious. But, after talking to a lot of engineers and customers, I realized that not everyone knows this trick. So here it is. The question is this: how to simulate a real host in a physical network environment when you don’t have computer at your disposal? Well, let’s take an example. The environment Here is an example with a very simple VXLAN topology consisting of two spines and two leafs. I’m using Cisco Nexus switches…

The post How to simulate a host in a real network? appeared first on AboutNetworks.net.

Basic Linux Networking tips and tricks part-5: tcpdump

tcpdump-logo

Here is another post of the series on basic network troubleshooting and tools under Linux. In this post, I will talk about tcpdump. Other posts of the series This post is part of a series of basic Linux Networking tips and tricks. The other posts of this series are: The ip and nmcli commands The mtr command The ss and netstat commands The curl command tcpdump Introduction I think the most essential element to debug a network problem is a packet capture tool or sniffer, and the most common one…

The post Basic Linux Networking tips and tricks part-5: tcpdump appeared first on AboutNetworks.net.

25 years as a Network Engineer!

Cisco-2501

In January 1996, I entered for the first time in the configuration of a Cisco 2501 router. This was the beginning of my career as a network engineer. That was just 25 years ago! Here’s a quick look back and a few tips for junior engineers who are at the beginning of their careers.   25 years as a Network Engineer! In 25 years, I had the opportunity to change several times my working environment and specialty as a network engineer: I went from network engineer and peering-manager for regional…

The post 25 years as a Network Engineer! appeared first on AboutNetworks.net.

Goodbye 2020… and never come back!

As we approach the end of the year, we can finally say goodbye to 2020. Goodbye 2020… and never come back! But, it is also time to look back at 2020 and try to see what the year 2021 promises us. So, in 2020…   COVID-19! The first thing that comes to mind when we talk about this year, and I think this will be the case for a long time, is the COVID-19! Who could have foreseen at the beginning of January that the entire world would be masked…

The post Goodbye 2020… and never come back! appeared first on AboutNetworks.net.

2020 IT Blog Awards finalist!

2020 IT Blog Awards finalist

I have the honor of having my blog selected as a finalist in the Most Educational category of the 2020 IT Blog Awards, hosted by Cisco. It is an honor and a great joy for me to be selected, for the third consecutive year, alongside other high-level bloggers who all have very deep technical knowledge! I hope you enjoy my articles as much as I enjoy writing and sharing them. I know I could write more, but I try to put quality ahead of quantity.   Please click here to vote…

The post 2020 IT Blog Awards finalist! appeared first on AboutNetworks.net.

How to Overcome the Impostor Syndrome as Network Engineer

imposter-syndrome

Many network engineers, myself included, sometimes feel like they don’t belong and don’t deserve to be here. Here are a few tips to combat the impostor syndrome. Sometimes, do you feel like an impostor? This is quite common in IT: you feel like an impostor. Even when you’ve got THE dream job, or when you’ve earned this recognition, or when you’ve passed that famous certification… You can’t get rid of the feeling that it’s just smoke, that you must have fooled everyone and that at any moment you will be…

The post How to Overcome the Impostor Syndrome as Network Engineer appeared first on AboutNetworks.net.

My Cisco DevNet Core Exam Journey

Cisco DevNet Specialist

On 23 October 2020, I took and passed the Cisco Certified DevNet Professional Core exam (350-901 DEVCOR) on my first attempt. I explain here the resources I used to study and pass this exam. My background and experience Before I explain what and how I have studied, you need to understand what I already knew, what was my background and experience with some of the topics of the exam before I started to study for it. At the end of April 2018, I already passed a Cisco specialist certification on…

The post My Cisco DevNet Core Exam Journey appeared first on AboutNetworks.net.

OnVue – Get certified from your home

OnVue

One of the positive aspects of this difficult period, if I may say so, is the possibility of taking a Pearson Vue test online, called OnVue. Last Friday, October 23rd, I took a Cisco exam from home and I think it’s interesting to share with you the details of this experience. With OnVue – Get certified from your home! The registration for the exam The registration for the test is almost the same as for a Cisco test done in a Vue test center. Go to the website of Pearson…

The post OnVue – Get certified from your home appeared first on AboutNetworks.net.

RDMA over Converged Ethernet (RoCE) on Cisco Nexus 9300

RoCE - Rocky

On a previous post, I made an introduction about NVMe, NVMe-oF and RDMA for network engineers. In this post, I’m going to talk about RDMA over Converged Ethernet (RoCE) and more specifically how to implement and configure the QoS part of RoCEv2 on the Cisco Nexus 9300 series. What is RoCE? RDMA over Converged Ethernet (RoCE – pronounced “Rocky”) is a network protocol that allows Remote Direct Memory Access (RDMA) over an Ethernet network. It does this by an encapsulation of an InfiniBand transport packet over Ethernet. There are two…

The post RDMA over Converged Ethernet (RoCE) on Cisco Nexus 9300 appeared first on AboutNetworks.net.

NVMe, NVMe over Fabrics and RDMA for network engineers

HDD

In the past, the evolution of network-based storage was not really a problem for network engineers: the network was fast and the spinning hard drives were slow. Natural network upgrades to 10Gb, 40Gb, and 100Gb Ethernet were more than sufficient to meet the networking needs of storage systems. But now, with the introduction of ultra-fast solid-state disks (SSDs) and Non-Volatile Memory Express (NVMe), this is no longer true! Storage teams now have the ability to potentially saturate the network with incredibly fast devices. Network-based storage (SANs) using NVMe technology –…

The post NVMe, NVMe over Fabrics and RDMA for network engineers appeared first on AboutNetworks.net.