Most Recent Writings

IPv6 6RD with Ubiquiti and DD-WRT

This posts walks through how to create an isolated network which has access to the IPv6 Internet via 6RD using Ubiquiti EdgeMax equipment and a router running DD-WRT. 6RD (Rapid Deployment) is a method to reach the IPv6 Internet by tunneling over an IPv4 network, similar to 6to4. While 6to4 is primarily used to connect different "IPv6 islands" together, 6RD was designed to ...
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Today I Passed the CCNA Wireless Exam

Wait, wasn't I just studying for the CCIE? After my lab attempt, I decided it was important to branch out a little bit and develop a more T-shaped skillset. I came from a generalist background (read jack-of-all-trades), then specialized in expert-level routing & switching which serves as a great foundation for other networking and infrastructure-related skills. Passing the CCNA Wireless ...
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MikroTik Automated MPLS L3VPN Lab

I am breaking out of the Cisco wheelhouse a little bit by using MikroTik RouterOS to build on my previous work of automating a base-level lab configuration. Working with another network operating system that uses a completely different syntax allows you to learn the various protocols in a more meaningful way (in my opinion). When you configure a single vendor's ...
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Easy Disaster Recovery Plan

DR plans encompass everything from no plan whatsoever (failing to plan is planning to fail), to active/active workloads distributed among several geo-redundant datacenters. This spectrum, just like nearly everything else in business, goes from zero to enormous cost and complexity. In the interest of keeping things simple, I designed a relatively inexpensive and uncomplicated enterprise DR plan that can be ...
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My First CCIE Lab Attempt

This is the unabridged version. The abridged version is available on LinkedIn. From the Written... Preparing, Part 1 Preparing, Part 2 Lab Day Part 1: TS Lab Day Part 2: DIAG Lab Day Part 3: CFG Aftermath Onward! From the Written... I passed the CCIE Routing & Switching v5.1 written exam in August 2017. It was a huge moment for ...
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Using Bridge Domain Interfaces on Cisco ASR-1K Routers

I am replacing an old Cisco 3945 router with a new ASR-1001X. The 3945, which has three gigabit Ethernet interfaces, has one connection to two service providers, and a single tagged link back to the network core carrying the traffic of a few different IP subnets. The ASR-1001X has six gigabit Ethernet interfaces, so when replacing the 3945 I wanted ...
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Automating Labs…Now With YAML and Multi-Threading!

The automation described in my last post had a couple of glaring flaws. I quickly discovered the inflexibility of using a CSV file for the data source as I started to add more variables to each device. The second flaw was that for approximately 30 devices, it took about 20 minutes to generate and push the device configurations, because each ...
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Automating Labs with Python, Jinja2, and Netmiko

Following up on my last post, I have set out to start automating certain aspects of my labs. I spent a few days going over the material from Kirk Byers' highly-recommend Python for Network Engineers course. I studied on the previous version of his course a couple of years ago (covering Python2), but this new version, which covers Python3, is ...
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Why Network Automation?

I have been wanting to get a little deeper into some various technologies surrounding MPLS and BGP-based VPNs (beyond basic L3VPN, such L2VPN, QoS, multicast, EVPN, etc.), so I assembled a virtual lab with approximately 30 routers which represent a service provider core and several "customer" sites, along with two sources of fake Internet connectivity (or more accurately, a simulated ...
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Mind Map for CCIE & CCNP Routing & Switching

I created a mindmap of topics that are covered on the current Cisco CCIE RSv5 lab exam to help myself study, and I thought my work might be useful to the general network community as well. I included CCNP R&S in the title, because there's a lot of overlapping information that I think most people pursuing the CCNP might find ...
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