Category: automation

The first car I got decades ago was a simple mechanical beast – you’d push something, and a cable would make sure something else moved somewhere. I could also fix 80% of the problems, and people who were willing to change spark plugs and similar stuff could get to 90+%.

Today the cars are distributed computer systems that nobody can fix once they get a quirk that is not discoverable with level-1 diagnostic tools.

I always encourage the students attending the Building Network Automation Solutions online course to create solutions for problems they’re facing in their networks instead of wasting time with vanilla hands-on assignments.

Francois Herbet took the advice literally and decided to create a solution that would configure PE-routers and create full-blown device configurations for CE-routers.

One of the beauties of VMware NSX is that it’s fully API-based – you can automate any aspect of it by writing a script (or using any of the network automation tools) that executes a series of well-defined (and well-documented) API calls.

To make that task even easier, VMware released PowerNSX, an open-source library of PowerShell commandlets that abstract the internal details of NSX API and give you an easy-to-use interface (assuming you use PowerShell as your automation tool).

Gabriel Sulbaran decided to tackle a pretty challenging problem after watching my Ansible for Networking Engineers webinar: configuring older Checkpoint firewalls.

I had no idea what Ansible was when I started your webinar, and now I already did a really simple but helpful playbook to automate changing the timezone and adding and deleting admin users in a Checkpoint firewall using the command and raw modules. Had to use those modules because there are no official Checkpoint module for the version I'm working on (R77.30).

Did you automate something in your network? Let me know!

A while ago Russ White (answering a reader question) mentioned some areas where we might find machine learning useful in networking:

If we are talking about the overlay, or traffic engineering, or even quality of service, I think we will see a rising trend towards using machine learning in network environments to help solve those problems. I am not convinced machine learning can solve these problems, in the sense of leaving humans out of the loop, but humans could set the parameters up, let the neural network learn the flows, and then let the machine adjust things over time. I tend to think this kind of work will be pretty narrow for a long time to come.

Guess what: as fancy as it sounds, we don’t need machine learning to solve those problems.

I don’t think I’ve ever been at a Tech Field Day event that’s been as intense as what we went through in the last few days at Cisco Live Europe – at least 17 different presentations in two days. It’s still all a blur and will take a long while to sort out.

First impressions:

It took years after NETCONF RFCs were published before IETF standardized YANG. It took another half-decade before they could agree on how to enable or disable an interface, set interface description, or read interface counters. A few more years passed by, and finally some vendors implemented some of the IETF or OpenConfig YANG data models (with one notable exception).

Now that we have the standardized structure, it’s easy to build automated multi-vendor networks, right? Not so fast…

While I have stock homework assignments prepared for every module of the Building Network Automation Solutions online course I always encourage the students to pick a challenge from their production network and solve it during the course.

Pavel Rovnov decided to focus on consistency of network management parameters (NTP, SNMP, SSH and syslog configuration) across Extreme and Cumulus switches, Fortinet firewalls and several distributions of Linux.

One of the first things I did when I started my deep-dive into network automation topics was to figure what tools people use to automate stuff and (on a pretty high level) what each one of these tools do.

You often hear about Ansible, Chef and Puppet when talking about network automation tools, with Salt becoming more popular, and CFEngine being occasionally mentioned. However, most network automation engineers prefer Ansible. Here are a few reasons.

Most engineers talking about network automation focus on configuration management: keeping track of configuration changes, generating device configurations from data models and templates, and deploying configuration changes.

There’s another extremely important aspect of network automation that’s oft forgotten: automatic response to internal or external events. You could wait for self-driving networks to see it implemented, or learn how to do it yourself.

Level3 had a pretty bad bad-hair-day just a day before Pete Lumbis talked about Continuous Integration on the Building Network Automation Solutions online course (yes, it was a great lead-in for Pete).

According to messages circulating on mailing lists it was all caused by a fumbled configuration attempt. My wild guess: someone deleting the wrong route map, causing routes that should have been tagged with no-export escape into the wider Internet.

It’s interesting how the same pundits who loudly complain about the complexities of BGP (and how it will be dead any time soon and replaced by an SDN miracle) also praise the beauties of intent-based networking… without realizing that the hated BGP route selection process represents one of the first failures of intent-based approach to networking.

Let’s start with some definitions. There are two ways to get a job done by someone else:

In the first few sessions of the Building Network Automation Solutions online course we used Ansible as the tool-of-choice because it’s the easiest automation tool to get started with. Now that we’ve established the baseline, it’s time to explore the alternatives.

In a live session on February 27th 2018, Mircea Ulinic will describe Salt, an open source, general-purpose event-driven automation framework that we briefly discussed in Episode 77 of Software Gone Wild podcast.

A while ago I created an Ansible playbook that creates network diagrams from LLDP information. Ben Roberts, a student in my Building Network Automation Solutions online course used those ideas to create an awesome solution: he’s graphing multicast trees.

Here’s how he described his solution:

For the first two sessions of the Building Network Automation Solutions online course I got awesome guest speakers, and it seems we’ll have another fantastic lineup in the Spring 2018 course:

Most network automation solutions focus on device configuration based on user request – service creation or change of data model describing the network. Another very important but often ignored aspect is automatic response to external events, and that’s what David Gee will describe in his presentation.