Network Troubleshooting From The User Perspective
When investigating a user's network problem, it's helpful to start your analysis near the client machine.
When investigating a user's network problem, it's helpful to start your analysis near the client machine.
Pyramids and cathedrals are so old school.
Most network automation tutorials out there assume you’re running Ansible on your workstation and accessing virtual machines via SSH ports mapped by Vagrant. That’s great if you’re an experienced Ansible/Python user; for a clunky beginner like myself it’s safer to run Ansible within a VM that can be destroyed and recreated in seconds.
I’ve been leveraging VIRL for some time to build and test self-contained labs. I’ve always known that there was some ability to connect to the world outside of this environment. Recently, I decided to configure this functionality and I wanted to take just a moment to share what I found.
First and foremost, this isn’t anything difficult or time consuming. So if you have a need to leverage physical devices with your VIRL deployment, don’t hesitate before building it out.
There are two mechanisms for outside connectivity. The first mechanism is called SNAT. This method basically builds static NAT in and out of the environment. I get how this could be beneficial, but I would typically prefer to keep any NAT configuration contained to an environment that I am very familiar with (possibly an ASA or IOS instance outside the lab when an additional NAT layer is required).
The second method, and configuration we will be testing is called FLAT. In this configuration, VIRL connects a L2 broadcast domain between a lab device and an Ethernet interface. In my example I am running the VIRL components in a VM environment on ESXi. So this is a virtual interface that needs Continue reading