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,
OSPF Convergence In a Hub and Spoke Topology
My dear friend Micheline Murphy posted an excellent question on OSPF in a Hub and Spoke topology at the Cisco Learning Network. The scenario is a Hub and Spoke topology with two Hub routers that are ABRs belonging to area
Catalyst SD-WAN – Introduction to Configuration Groups
One of the challenges with Catalyst SD-WAN is managing templates. Depending on how successful you are in standardizing your deployment, you risk ending up with many device templates. This can also be amplified if you have several platforms as each
Catalyst SD-WAN – Bootstrapping a Catalyst8000v Using a File on Bootflash
Yesterday I showed how to bootstrap a Catalyst8000v from the CLI. Today, I will show how to put a file on bootflash which includes the configuration but also the root certificate and the certificate of the device. This is a
Catalyst SD-WAN – Botstrapping a Catalyst8000v in a Virtual Lab
I’m rebuilding my Catalyst SD-WAN lab and thought I would give some quick pointers on how to bootstrap a Catalyst 8000v in your virtual lab. When the router first boots up, it will be in autonomous mode (non-SD-WAN mode): Configure
Building a WAN Impairment Device in Linux on VMware vSphere
In some scenarios it is really useful to be able to simulate a WAN in regards to latency, jitter, and packet loss. Especially for those of us that work with SD-WAN and want to test or policies in a controlled
Microsoft AZ-700 completed
I just passed the Microsoft AZ-700 exam, Designing and Implementing Microsoft Azure Networking Solutions, which means I am now certified in the two major clouds (AWS and Azure) when it comes to networking. As always after an exam, I write
Is VLAN 1 Special in Cisco Networks?
I got asked why we change from VLAN 1 to another VLAN in Cisco networks. What is bad with the default setup? Is VLAN 1 really magical in a Cisco network? When Cisco ships a Catalyst switch to you, there
Internet Edge IP SLA Deep Dive
It is a common design to have an internet Edge router connected to two different internet service providers to protect against the failure of an ISP bringing the office down. The topology may look something like this: The two ISPs