Words

Posted on January 5, 2023

Recently, I started looking into testing and validating network configurations leveraging Batfish, Pandas and pytest. Doing something with Batfish has been on my to-do list for quite a while. After playing with it, I can say it is a real pity I did not start using this tool earlier. [Read More]

Posted on June 2, 2022

A good deal of Python, or at least CPython, is written in C. The language and the interpreter are implemented in C and in addition to this, you can also find a lot of modules in the Python standard library powered by C. [Read More]

Posted on January 12, 2022

Even though there are a lot of resources on rendering and building network configurations, I was missing content that describes the pattern that I have been using for some time now. This post outlines the pattern I have been using and provides a toy example where that pattern is implemented.... [Read More]

Posted on November 18, 2021

Calling Rust code from Python is made easy by PyO3. You can write a Rust library and rely on the combination of PyO3 and maturin, a supporting tool from the PyO3 ecosystem, to compile the Rust library and have it installed directly as a Python module. Among others, PyO3 can... [Read More]

Posted on November 6, 2021

Python is a fantastic language! At least, in my opinion it is. There is a great ecosystem of libraries that you can use and I find it a very satisfying language to work with. But being the interpreted language that it is, Python is not the fastest. To speed things... [Read More]

Posted on September 1, 2021

A thorough understanding of the Option enum and the Result enum are essential to understanding optional values and error handling in Rust. In this ariticle, I will work my way through both of them. [Read More]

Posted on August 15, 2021

What is a vector: [Read More]

Posted on August 14, 2021

In Rust, the slice is a primitive type as well as a sequence type. I found slices very confusing at first. In the Rust book, slices are defined as ‘a dynamically-sized view into a contiguous sequence’. [Read More]

Posted on August 12, 2021

The Rust tuple is placed in several categories of types. For starters, the tuple is a primitive type. Among others, this means tuples have the Copy trait implemented, making them pass by value. [Read More]

Posted on August 6, 2021

Creating small CLI tools is a fun way to get more familiar with a programming language. If you are coming from an infrastructure background, a CLI tool that you can use to send commands to devices/servers might be considered a neat starting point getting into Rust. This is how I... [Read More]

Posted on August 5, 2021

In Rust, the array is the simplest of the sequence types (the others being slices and tuples). The array lives on the stack and has a fixed length. The length you declare an array with is part of it’s type and it is going to remain the same throughout the... [Read More]

Posted on August 4, 2021

Scalar types [Read More]

Posted on May 17, 2021

GoSNMP is a very fun package to play with and learn about Go. It is easy to use and it can be made into doing something usefull quickly. The examples in the repo are clear and SNMP offers a fun way to play with channels and retrieving information from devices.... [Read More]

Posted on April 2, 2021

A little while ago, I decided to start learning Go. One of the things that I wanted to start out with was learning how to work with JSON. Coming from Python, the first thing I noticed was that working with JSON in Go is a bit more involved. [Read More]

Posted on March 5, 2021

The schedule module describes itself as ‘Python job scheduling for humans’. It is a nice package that I use for infrastructure related tasks and activities. The package (currently) prides itself for the following: A simple to use API for scheduling jobs. Very lightweight and no external dependencies. Excellent test coverage.... [Read More]

Posted on February 18, 2021

Many people dread XML and would rather work with JSON. However, XPATH can be extremely powerful when dealing with the Juniper XML API output. [Read More]

Posted on December 24, 2020

In some cases, Jinja templates become too complicated. Lots of deeply nested if statements, clunky ways of working with variables, macros and many other things that hurt the eyes. [Read More]

Posted on December 6, 2020

In the search for a framework that would allow me to plug my automations without too much fuss, I came across Nornir. I have been enjoying it so much that I decided to do write down an introduction for others. My hope is that this post will allow others to... [Read More]

Posted on August 13, 2020

JSNAPy allows you to create snapshots that capture the state of devices running Junos. After capturing the device state, you can run tests against these snapshots. These tests can tell you if there is something to worry about or not. [Read More]

Posted on July 3, 2020

Google TextFSM is a Python module that is written to make parsing text easier. It is a convenient way to turn CLI output into structured data. This blog covers a TextFSM example and shares the way in which I have been using TextFSM lately. [Read More]

Posted on June 12, 2020

When you log in to a Juniper device, you normally land on the Juniper CLI. This is the command shell that most engineers are familiar with. But not all commands are available on the Juniper CLI. Sometimes you will need to interact with the shell of the underlying OS, which... [Read More]

Posted on June 8, 2020

Recently, I have been looking into a Python library called scrapli. You can use it for screen scraping and what led me to checking out this package is the fact that it is easy to tap into ssh2-python. This can offer quite some benefits in terms of speed and CPU... [Read More]

Posted on May 15, 2020

Some examples on working with YAML (‘YAML Ain’t Markup Language’) in Python3. In the examples, I am using PyYAML version 5.2 which can be installed using pip3 install pyyaml. [Read More]

Posted on May 4, 2020

A LAG combines multiple physical links between two adjacent nodes together to establish a single (virtual) link. This offers increased bandwidth, link efficiency and physical redundancy. [Read More]

Posted on March 20, 2020

Diving into SaltStack for the first time can be difficult and confusing. There is a lot of terminology involved that is going to be new. This makes it difficult to get a clear overview of how everything is working together and how the different parts might be useful to you.... [Read More]

Posted on February 22, 2020

Cisco IOS XR has an XML API you can use to retrieve structured data from the device. In this article, I will run through several examples on how you can do this with Python. I will use the backend NAPALM library called pyIOSXR to issue RPCs. I’ll also show some... [Read More]

Posted on January 31, 2020

Recently, I have been exploring NAPALM in relation to NX-OS. To connect to the device, I used the nxos driver which uses the NXAPI. This write-up contains some of the basic operations. I am using NAPALM version 2.5.0 and the NX-OS device is a Nexus7700 running 8.0(1). [Read More]

Posted on January 17, 2020

This article contains several examples I could have used after reading up on the basics in Python. After I read the first chapters of Automate the Boring Stuff with Python and Learning Python, 5th Edition, I struggled to put the concepts I read about into practice. I understood the basic... [Read More]

Posted on December 30, 2019

Extending the Junos PyEZ Device class with my own subclass helped me to more easily reuse my code and it made my scripts less of a clutter. This article is a short example on how to do this. [Read More]

Posted on December 23, 2019

Last week, I was doing some troubleshooting in a lab when I noticed one of the proxy minions refused to go into configure mode. The approach I took when I was troubleshooting this was a very general one that works for all proxy minion types. For this reason, I thought... [Read More]