Valley-free routing is a concept that may not be well known but that is relevant to datacenter design. In this post, we’ll valley-free routing based on a leaf and spine topology. There are many posts about leaf and spine topology
Nexus9000v and “Missing” Routes
I have built my lab for VXLAN on the Nexus9300v platform. Since I have a leaf and spine topology, there are ECMP routes towards the spines for the other leafs’ loopbacks. When performing labs though, I noticed that I didn’t
Is One Protocol Simpler Than Two?
I’ve been in a lot of interesting discussions the last couple of days on what protocol to use for the underlay when building a VXLAN datacenter network. Do you use an IGP such as OSPF or ISIS or do you
Choosing the Underlay Protocol in a VXLAN Network
When building a VXLAN network, what are the considerations for choosing the underlay protocol such as OSPF, IS-IS, or BGP? You obviously want the design to be supported by your vendor of choice. Your staff should also be able to
Unnumbered Links In OSPF
This post is going to be a real deep dive! First, I want to send my sincere thanks to the maestro Peter Palúch and the guru Ivan Pepelnjak for helping me research this topic. Ivan wrote a couple of great
Building a VXLAN Lab Using Nexus9000v
As I dive into the world of VXLAN, I will need a lab as that is the best way to deepen the learning process and to get hands-on experience with a protocol. I will be building a Cisco Nexus9000v lab
Caveats When Deploying Nexus9000v
As I’m building a VXLAN lab based on Nexus9000v, I ran into some caveats while deploying. Some things are related to ESX (vSphere) only while others apply to also other platforms. The boot process for Nexus9000v is a bit special.
Introduction to VXLAN
In the previous post, we looked at some of the challenges with L2-based networks. Now let’s start diving into what VXLAN is and what it can provide. First, let’s talk about overlays. Overlays Overlays are not new. We have had
VXLAN/EVPN – What Are the Challenges in L2-based Networks?
Before diving into a new technology, it is always useful to understand the previous generation of technology, what the limitations where, and how the new technology intends to overcome them. In this post, let’s look at what some of the
Python – Using the IP Address Module to Calculate IPs
I’m currently preparing for a network rollout and the preparation includes assigning subnets to the sites. There are subnets needed for management, wired users, wireless users, guests, and so on. Once subnets have been assigned, for some of the subnets,