nullzero

EVPN

EVPN-VXLAN Explainer 5 - Layer 3 with Asymmetrical IRB

Thus far, this series of posts have all been about Layer 2 over Layer 3 models; the customer ethernet frames encapsulated in UDP, traversing L3 networks. The routing has been confined underlay, the customer traffic has stayed within the same network. No longer! In this post, things start getting a

EVPN

EVPN-VXLAN Explainer 4 - Route Type Three and Auto-Discovery

In this post we will have a look at another EVPN Route Type, that being RT-3, which goes by the rather opaque name of 'Inclusive Multicast Ethernet Tag'; and look at how it is used to ensure EVPN peers flood traffic to those neighbours that need it. Firstly, we'll look

EVPN

EVPN-VXLAN Explainer 3 - BGP UPDATE & Route Type 2

The story so far * In post 1 we looked at VXLAN, an encapsulation type that enables L2 traffic to traverse L3 networks, the use case being virtual overlay networks to provide connectivity to VMs and containers. * VXLAN alone uses data plane learning to build a view of the MAC addresses

EVPN

EVPN-VXLAN Explainer 2 - The BGP Session

In this second post I will look at Ethernet VPN (EVPN), what is it and how to configure a BGP EVPN session on Aruba devices. Please note, this post will focus on the establishment of the BGP EVPN session between peers, and thus will not present a fully functioning EVPN

EVPN

EVPN-VXLAN Explainer 1 - Static VXLAN

In this series of blog posts I'm going to break down how to configure Aruba AOS-CX switches for VXLAN and EVPN, plus explain how to read the EVPN table and various 'show' commands. In this first post I will look at VXLAN, its configuration and operation. A note about EVPN-VXLAN

Docker, Openvswitch & Aruba VXLAN Network Build

This blog provides details of how to build a static VXLAN network that connects physical hardware to a virtualised network, enabling communication from docker containers to external nodes. The build is comprised of a hardware ArubaOS-Switch acting as a VTEP and an openvswitch VTEP running on an ubuntu server, which

IPv6

"What's your IPv6 strategy?"

For many in enterprise networking, IPv6 is just a distant memory of a tedious mandatory training a few years back. Weird addresses, over-eager trainer, stories about v6 adoption that never came true. Why then for the last couple of years have I been presenting to Aruba audiences about IPv6 adoption?

IPv6

IPv6 SLAAC Host OS Address Allocation

While rebuilding my v6 lab with a variety different host OS, I found that there is no single approach to address generation in IPv6 SLAAC networks. I've recorded my findings below for future reference, but also as a good way to delve deeper into the murky world of IPv6 address

network automation

Why I'm telling network engineers to learn Python

During a wet autumnal walk, I was explaining to my girlfriend about my recent presentations. I've been doing my 'Getting Started with Python' talk at Aruba Airheads meet-ups. I recorded an early version of it, see below. One point I mentioned is that the reaction is always mixed. When I

IPv6

Android does not support DHCPv6 and Google 'Won't Fix' that

> Since 2012 there has been a ticket open on Google's public 'Issue Tracker' requesting Android support DHCPv6 [https://issuetracker.google.com/issues/36949085]. On 6th November the status of the issue was changed to 'Won't Fix (Intended Behavior)'. The fact that Android does not support DHCPv6 may come as

network automation

Windows for Network Automation?

The OS landscape is changing and, yes, you can learn and run network automation tools on Windows. After a hot, dry June day in Richmond I boarded an empty train. It being just myself and a couple opposite we struck up a conversation, awaiting the train’s departure. Over the

python

Workshop Epilogue 2

Networkers and Coding Q & A In Part One of this blog I mentioned that I liked to start the second day of the workshop a little differently. The workshop itself was aimed very much at network engineers but the second day was all about using Python to interact with the

network automation

ArubaOS-CX Workshop Epilogue

12 sessions, 6 countries, 4 months After twelve sessions across six countries over four months, last week we presented the final ArubaOS-CX EMEA workshop in Dubai. The objective of the session was to familiarise the attendees with the game-changing ArubaOS-CX operating system and 8320 switching hardware. Each workshop was split

Building an Ansible Sandpit using Vagrant

Vagrant SSH connections are built for host to box, not box to box. In this post I detail how to fix this with an aim to build an Ansible sandpit. Ansible and Vagrant Before I start using Ansible with network devices, I thought I should get to know it in

Ansible Install: Ubuntu vs. PIP vs Fedora

Aim I'm trying to write a simple 'how to' for the build of an Ansible 'sandpit' environment that my networking colleague can follow. I want this to have minimal demands in terms of prior knowledge about linux, git and OS package management. What's the problem? * Ansible control machine is not

python

My Video Adventures across the ArubaOS-CX Spectrum

Hungry Horace For the uninitiated, ArubaOS-CX is a new networking OS, running on Aruba's 84/830xx campus core switches. I've been playing around with the OS for a while now. The headline is 'network OS with auto-generated REST API'. No clunky abstraction layer, no patchy feature coverage. Just the whole

python

Python Reading List

My Python recommended reading list.

The internet is a series of (you)tubes

As I delve further in python and network automation I've made a couple of series focusing on python and the ArubaOS-Switch API. Python and REST APIs This series is comprised of four videos. From building an work environment, performing a GET, a POST and finally doing something with the data.

networking

IPv6 Security Workshop (plus free sandwiches)

> A free workshop in London on IPv6 Security, hosted by the UK IPv6 Council? I'm in. This is a write-up of the recent IPv6 Security Workshop held at the BT Centre, London, by the UK IPv6 Council. My buy-in In my previous role as PoC runner I performed a few

network automation

Moving Beyond CLI

Hello, here's a link to a youtube video that I made this week. It is a screen-capture of a preso that I gave at Aruba Atmosphere in Disneyland Paris: One area that I do not think I provide enough detail is the difference between screen-scraping and using an API; structured

python

Getting into Python: A Guide for Networkers Part 2

This is a very subjective piece about what worked for me when I first tried my hand at getting into Python as a networking chap. It comes with the disclaimer that your experience may be wildly different. Commit Firstly, and most importantly, commit to learning Python, keep focused on that,

python

Getting into Python: A Guide for Networkers Part 1

> No, you are not mistaken, it is 2017 and I'm writing this blog about networking types learning python. I understand that this may all sound a little 2012 but I think I've actually got good reason to write and encourage other like-minded network engineers to get into learning python. But

Adventures in youtube

At this point I haven't update this blog for about 6 months and this post stands as a 'What I've been up to' report. "Pass me my branded baseball cap!" AKA corporate blogging Over the summer I did a bit of corporate blogging for my employer, HPE Aruba, on their

Openswitch, Docker & Linux Networking - Part 2: Build a Network

EDIT 01Nov2016 It looks like openswitch is going through a reboot of sorts, hard, soft, whatever, I'm not sure how relevant this information is anymore. I'll leave it up as an archive but be warned that this may be as irrelevant as the Lucas plot points for Episode 7. In

Openswitch, Docker & Linux Networking - Part 1: Build an image

EDIT 01Nov2016 It looks like openswitch is going through a reboot of sorts, hard, soft, whatever, I'm not sure how relevant this information is anymore. I'll leave it up as an archive but be warned that this may be as irrelevant as the Lucas plot points for Episode 7. Is