Exams 1. Cisco Certified DevNet Expert Lab Exam Overview

Hello my friend,

Recently Cisco has finally announced the expert level certification in their automation and software development track named DevNet. The idea behind this certification track is to promote the DevOps mindset and culture in the traditional network engineering and to give the necessary theoretical knowledge and practical skills for engineers to start developing, maintaining and supporting network automation in Cisco Networks.

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Brief Description

This Lab exam allows the one to earn the Expert level certification, provided the individual has already passed the theoretical exam DevCore (350-901 Developing Applications using Cisco Core Platforms and APIs). The expert level certification from Cisco is often very attractive for networking engineers as it generally well-respected across the industry and acts as a guideline of what engineer at a certain level is expected to know. The DevNet certification is yet relatively young and finding its path, as it steps in the area where it is competing with some Continue reading

Automation 5. Running Python (MicroPython) Scripts with pySROS Directly on Nokia SR OS Network Devices

Hello my friend,

We have already reviewed how to collect the operational and configuration data from Nokia SR OS devices, and even how to structure it in YANG trees, as well as how to configure network devices with Python and pySROS. You may think, that all the interesting things about Nokia pySROS are already covered. Well, we have some more aces in the pocket for you. Today you will learn some new things, such as MicroPython and how to run the pySROS code directly on Nokia SR OS based network functions.

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Network Automation Is So Popular These Days… Shall I Do Something Different?

Network Automaton is indeed getting more and more popular. There are a few reasons for that: one the one hand, networks getting more complex with all fancy SDx technologies (SDN, SD-WAN, SDA, etc); on the other hand, it is required to deliver new services quicker and quicker. Doing the things manually Continue reading

pygnmi 12. pyGNMI CLI to Explore GNMI Capabilities of the Network Devices

Hello my friend,

For a a while we were silent about pyGNMI; however, it doesn’t mean that the project is abandoned. Actually, it is quite opposite: we are very delighted and thankful for the community that we have a number of contributors from the whole world, who is taking part in the pyGNMI project and committing new code. Thanks to the community, a few new features were added as well as a number of bugs fixed. And today we will take a look one of such community-added features, which is called pygnmcli.

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Is GNMI a Good Interface for Network Automation?

Yes, it is. GNMI is one of the most recent interfaces created for the management plane, which allows you to manage the network devices (i.e., retrieve configuration and operational data, modify configuration) and collect the streaming or event-driven telemetry. Sounds like one-size-fits-all, isn’t it? On top of that, GNMI supports also different transport Continue reading

Automation 4. Extracting and Exploring 6WING YANG Modules with NETCONF, Pyang and Ansible

Hello my friend,

Some time ago we’ve explained how to deploy a 6WING vRouter in a Linux environmennt, such as our Open Source Virtualised cloud with Debian Linux and ProxMox. One of the good things about 6WIND is that its configuration is entirely based on YANG modules and is exposable via NETCONF. Today you will learn how to get 6WIND YANG modules, how are they structured with Pyang and how to automate its extraction with Ansible.

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Why Is Everyone so Passionate about Model-Driven Automation and YANG?

All we love nice configuration files made in easy readable YANG or JSON, isn’t it? The beauty of working with them is that you don’t need to create a text string parsers, which is always a difficult task. One of the reasons, why it is so difficult to create parsers, is because of ever changing CLI structures and also values in the semi-formatted text, our ascii tables we see Continue reading

Automation 3. Configuring of Nokia SROS via NETCONF/YANG with pySROS and Python

Hello my friend,

we continue the review and tutorial of pySROS, the Nokia Python library to manage the Nokia SR OS based routers via NETCONF/YANG. In previous blogposts we’ve covered how to poll the configuration and operational data and how to structure the received data and explore its YANG modules. Today we’ll take a look how to configure Nokia SR OS based devices.

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I Have Software Developers in My Company. Why Should I Do Automation?

This is one of the trickiest questions, which doesn’t have a simple answer. Really, why should you, network or security engineer, bother yourself and step into completely new and unknown world of automation and development? The reason for that very simple: network and security automation (and infrastructure automation in general) requires detailed knowledge of the network and security infrastructure first of all. We always say at our trainings: automation is automation of your knowledge and skills. So

On top of that, Continue reading

Infrastructure 3. Deploying High Performance Pure Virtual Linux Router – 6WIND

Hello my friend,

Network Function Virtualisation (NFV) is not a new topic. There are numerous blogpost and articles, even in our blog, which review this topic. Yet, there is much more we can cover. Today we’ll share some insights on one of the very interesting products existing on the market today: 6WIND vRouter Turbo Router. We have a limited amount of days to write a few articles under our evaluation license. Hence, we’ll focus only on the most critical elements.

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Is Linux Suitable for Automation?

It absolutely is. In fact, Linux is the real home for automation systems, as in many cases it hosts the tools you create in Ansible, Python, Bash, Go or any other language. At the same time, in order to effectively work with Linux, you need to know how to automate management and operation of Linux operating system itself. And you will be absolutely capable to do that, once you attend our Continue reading

Automation 2. Exploring Nokia SR OS configuration in a programmable way with pySROS

Hello my friend,

Thanks a lot for all your interactions over our last post, it was very good feeling. As it attracted your attention, we decided to explore this topic further. Today we’ll focus on two main aspects: how you can figure out from Nokia SR OS CLI, what is your path to use in pySROS and how you visualise a configuration tree following YANG module.

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I Have Heard, Facebook Automation Caught It, Isn’t It?

Facebook outage happened the last week caused a lot of discussions, how reliable automation is in general and if there are too much automatons these days already in the infrastructure systems. Really, if Facebook with their smartest network and automation engineers failed, should I stay far away from automation? We believe, everyone will find his or her answer. From our perspective, we know that Facebook will make their systems after failure more robust and working. By the way, in our training Continue reading

Automation 1. First impression from pySROS – new Python library for automation of Nokia SR OS devices

Hello my friend,

For quite a while we were silent (literally, the last post was month ago), as we were busy with extremely busy with completion of an important customer engagement. It was successfully completed and we are back on track with writing new interesting and useful (we hope so :-)) materials for you! And today we talk about our favourite topic – automation. To be precise, automation of Nokia SR OS devices with a new Python library called pySROS created by Nokia folks.

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Why Is That Useful for Me?

If you have ever been in a situation, when there are much more work than hours in a day, then you know how important is to be able to do the job quickly and accurately. It is even better, if such job is done not by yourself, but rather by someone else or something else. This is exactly, where the automation of network and Continue reading

pygnmi 11. Measuring Automated Testing with Coverage.py and Pytest

Hello my friend,

It is been a while since we posted our last blogpost, which was touching Infrastructure aspects of building Multi Server Cloud with ProxMox. After summer break we continue our blogging and developing activities at Karneliuk.com. Today we’ll show some backstage of the software development of the pygnmi.

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What is Automation? Network Automation?

In a nutshell, Automation and Network Automation are just subset of tasks from a broader topic called Software Development. With the move of the world towards Industry 4.0, the digital economy growth and others, all sort of applications are becoming more widely used. In order you create a history, and not being a part of that in the past, you shall know the principles of software development and be able to create applications yourselves. Sounds complicated? It may be, indeed. However, with our Network Automation Training you definitely will have a break-through in the software development world.

At our Continue reading

Infrastructure 2. Building Multi Server Cloud with Proxmox (Debian Linux) and Local Storage

Hello my friend,

In the previous blogpost we covered the installation of Proxmox as a core platform for building open source virtualisation environment. Today we’ll continue this discussion and will show how to create a multi server cloud in order to better spread the load and provide resiliency for your applications.

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How to Automate Infrastructure?

In many cases, Linux is a major driving power behind modern clouds. In fact, if you look across all current big clouds, such as Amazon Web Services, Google Cloud Platform, Microsoft Azure, you will see Linux everywhere: on servers and on network devices (e.g., data centre switches). Therefore, knowledge how to deal with Linux and how to automate it is crucial to be successful in automation current IT systems.

At our trainings, advanced network automation and automation with Nornir (2nd step after advanced network automation), we give you detailed knowledge of all the technologies relevant:

• Data encoding (free-text, XML, Continue reading

Infrastructure 1. Building Virtualized Environment with Debian Linux and Proxmox on HP and Supermicro

Hello my friend,

Just the last week we finished our Zero-to-Hero Network Automation Training, which was very intensive and very interesting. The one could think: it is time for vacation now!.. Not quite yet. We decided to use the time wisely and upgrade our lab to bring possibilities for customers to use it. Lab upgrade means a major infrastructure project, which involves brining new hardware, changing topology and new software to simplify its management. Sounds interesting? Jump to details!

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What is Infrastructure Automation?

Each and every element of your entire IT landscape requires two actions. It shall be monitored and it shall be managed. Being managed means that the element shall be configured and this is the first step for all sort of automations. Configuration management is a perfect use case to start automating your infrastructure, which spans servers, network devices, VMs, containers and much more. And we are here to help you to do Continue reading

pygnmi 10. Rapid and Reliable Network Testing with Pytest, Pygnmi, and OpenConfig

Hello my friend,

Talking to some our partners, they mentioned that they are extensively using the unit tests python libraries for the development of the software in Python. They are creating their applications in Django framework; therefore, they are using a built-in Django testing library, which is based on Python’s standard unittest. We start looking, how we can use that ourselves…

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Can This Help with Automated Network Assurance?

What do we, network engineers, do to quickly check that our network devices are reachable? We do ping. However, is that really good enough to check that your devices are OK? The one could say: I don’t even use a ping for that, as I rely on my NMS. This is also a good answer. In the same time, though, the vast majority of the NMS doesn’t contain all the details of network devices configuration and their operational data: e.g. all the details of OSPF and Continue reading

Bash #1. Automating Troubleshooting (Cumulus) Linux Networking

Hello my friend,

Very often at our zero-to-hero network automation training we are asked, what is the benefit of Bash? Why do we need to know Bash, if everyone is talking about Bash? The question is absolutely legitimate. One of the interesting and also legitimate answers I’ve just figured the last week.

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Do you finally write about network automation?

Everything in your network and IT operational processes can be automated. It is just matter of the resources (time, money, efforts) you spent on that against the gain you are obtaining. Basically, that is something what financial guys and girls call ROI (Return On Investments). The bigger the outcome and the lower the effort, the better the overall automation solution.

In our automation trainings we explain various use cases and success (and failure) strategies, how to build the (network) automation systems and tools, to make sure your gain is maximum. Our instructors have an extensive experience building Continue reading

Network Analysis 2. Analysing Network Configuration Consistency (Sanity check, BGP, Routes) with Batfish for Cisco, Arista, and Cumulus

Hello my friend,

In the previous blogpost we’ve introduced the Batfish and how to set it up. Today we’ll take a look how to perform the analysis of the configuration to figure out discrepancies, which may lead to broken operation of your network.

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Network Analysis as Part of Automation?

In software development we have a concept called CI/CD (Continuous Integration/Continuous Delivery). In a nutshell, it’s a methodology, which incorporates mandatory testing of configuration (code, software version, etc) before bringing it to production. The main idea behind it is that automated testing and validation will make sure that code is stable and fit for purpose. Automated testing? That’s where the automation comes to the stage.

And automation is something what we are experts in. And you can benefit from that expertise as well.

In our network automation training we follow zero to hero approach, where we start with the basics including Linux operation and administration topped with Continue reading

Network Analysis 1. Setting up and Getting Started with Batfish in Multivendor Network with Cisco, Arista, and Cumulus.

Hello my friend,

The new year we start with a new topic, which is a configuration analysis of the multivendor networks. We have a passion both to create our own open source tools and to use existing, creating by other teams and project. Today we will start dive in one of such a tool.

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Network analysis as part of automation?

In software development we have a concept called CI/CD (Continuous Integration/Continuous Delivery). In a nutshell, it’s a methodology, which incorporates mandatory testing of configuration (code, software version, etc) before bringing it to production. The main idea behind it is that automated testing and validation will make sure that code is stable and fit for purpose. Automated testing? That’s where the automation comes to the stage.

And automation is something what we are experts in. And you can benefit from that expertise as well.

In our network automation training we follow zero to hero approach, where we Continue reading

5 years on air.

Hello my friend,

Have we thought 5 years ago that we would manage to keep the blog running for such a long period of time and would create such a huge amount of useful information for the community? Definitely not. And that’s why it is even important we managed to achieve such a milestone. Thank a lot each of you for your support, ideas, feedbacks, shared on social medias and likes! That means a lot for us. Please, continue doing so

The last 12 month were absolutely incredible. The COVID-19 pandemic struck word so much that noone could ever believe. As a result, we, pretty much as a whole work, worked from home all past 12 moths… Which was an unusual experience. However, we used this time (in fact, due to no necessity to spend time on commute, we have more time to work) productively working on various projects for you, our dear readers. So, what have we managed to achieve?

Network Automation and Programmability Fundamentals with Cisco Press

One of the massive achievements was to complete the book Network Automation and Programmability Fundamentals, which was published by Cisco Press in May 2021. The journey for us started back in Continue reading

Tools 8. Visual Analysis of the Network Path with Open Source Databases and Python

Hello my friend,

Over the past several articles we have taken a look into the most popular tools for the network troubleshooting. To be precise, we have covered an approach to find your public IP address in a programmable way, how to measure your Internet connectivity speed with Speedtest, how to measure the connectivity speed between your endpoints using iPerf, rapid check of hosts presence in the network with fping, how to check the quality of the path through the network with MTR, and how to see what are in the packets you have in your network. Covering these tools for you and sharing ideas about automation with them led us to creating a new open source tool, which we are happy to share with the community. This time we decided not to think long on its name and just called it the Traceroute Analyzer.

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What is the network automation?

Continue reading

Tools 7. Show me your packets … with TCP dump

Hello my friend,

When something goes wrong with the distributed application, where the network is involved (e.g., between client and web service, or between frontend and backend of services), the network is a first thing to be blamed. After the troubleshooting, it is often turned out that the network is innocent, but we need first need to prove it.

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Automated troubleshooting for automated networks?

The truth is that automation helped me so many times to figure out the root cause of the network outages or malfunctions that I even stopped counting that. I may say that automaton solutions work perfect, if you create them to solve your issues and tailor to your environment.

That’s what our Live Network Automation Training (10 weeks) and Automation with Nornir (2 weeks) are all about: to show you real automation in a real environment with multiple vendors together. No matter what those vendors are, the automation principles, tools Continue reading

SP. Part 9. Health check of Segment Routing Traffic Engineering (SR-TE) tunnels with seamless BFD in Nokia SR OS

Hello my friend,

For a long time we haven’t posted blogs about pure network technologies. However, recently we were working on some interesting use case, which so far is not yet covered at a level of the working details nowhere in the internet. As such, we decided to share with you our findings and working details.

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How automation can help with SR-TE in SP network?

In some (big) networks the BGP-SR-TE is a good signal the SR-TE policies, so that the PE routers can build the SR-TE tunnels without the need to configure them locally. However, the BGP-SR-TE requires a full pledged SDN controller, so that you can generate the SR-TE policy in the backend using some UI/API and send the policies down to the network elements using the BGP. If you want to have a somewhat simpler setup, you may need need to deploy the tunnels manually. In this case, the automation is your closest Continue reading

Visualise and Analyse Your Data Centre Fabric with HAWK

Hello my friend,

Some time ago in LinkedIn we announced that we are working on the tool, which will allows you to model and analyse your network. As one of our primary focuses is data centres, we started from there. Despite it is an early stages, but we are happy and proud to introduce you HAWK: Highly-efficient Automated Weapon Kit. For now, this is a collection of the tools for the network management and analysis, but probably later we will put it under a joint hoot of some front-end, who knows…

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Where is the the border between network automation and software development?

In order to automate any network operation, you need to write a script, even if that is a simple one. On the other hand, any script is a program or software. This means that the creating of the scripts for the network automation is a form of the software development. And it is fun. Continue reading