Author Archives: David Varnum
Author Archives: David Varnum
TLDR; Keep your eye on Meter, a Network-as-a-Service company with a vision so far in the future that it seems nearly impossible, yet they are actively...
The post Meter sets the bar for Network-as-a-Service appeared first on /overlaid.
In its most rudimentary terms, a digital twin in the realm of networking is the concept of emulating or simulating a like-for-like topology of a production...
The post The network digital twin GOAT appeared first on /overlaid.
The topic of AI in the networking space has quickly moved from “what if” to “how soon”. Every major networking vendor is leveraging some aspect of...
The post Selector is evolving the way we operate networks appeared first on /overlaid.
Most network automation journeys start with building custom scripts and integrations, validating use cases, and getting value from low-hanging fruit. This is the fun part! However,...
The post Brief: When to consider Anuta Networks for automation appeared first on /overlaid.
Network engineers, even those that have adopted a developer mentality, often struggle with getting to that next evolution of self-service in on-premises data centers. We have...
The post Evolved on-prem networking with Netris appeared first on /overlaid.
Doing Infrastucture-as-Code (IaC) with Ansible has given me a headache – so I’ve recently been playing around with Terraform as an alternative to Ansible for certain tasks that require Cloud IaaS interactions. The goal of this blog post is to build an HA-VPN solution between GCP and an on-premises Cisco IOS-XE device (CSR) using Terraform. […]
The post Terraform an HA-VPN between GCP and Cisco appeared first on Overlaid.
Ansible, Nornir, and other automation frameworks are excellent for generating and deploying configurations in an automated fashion. In Ansible, you can run a playbook, loop through hosts in your inventory file, and deploy configurations with host-specific information by leveraging host_vars and group_vars. Unfortunately, as your automation environment starts to grow and become more critical, you’ll […]
The post Using Ansible and NetBox to deploy EVPN on Arista appeared first on Overlaid.
We often compare ourselves to others around us. We are impressed with the skills others possess, the content others produce, the appearances others maintain, the successes others have achieved, the feats others have conquered. This constant comparison can lead to melancholic states of ambivalence, and sometimes depression due to the artificial expectations of who we […]
The post Applying Essentialism to certifications and skills development in the Tech Industry appeared first on Overlaid.
Architecting for the cloud is becoming a highly desired skill set. Working as a consultant, I’m often in situations where clients are overwhelmed with questions about the cloud. How do I migrate my applications? How do I secure everything? How does it integrate with LDAP and DNS? What’s the best way to connect to the […]
The post Becoming an AWS Certified Solutions Architect Associate appeared first on Overlaid.
In the previous two blog posts, I covered the concepts of EVPN and shared a detailed configuration example on Arista EOS. In this blog post, I’ll be covering how to automate the deployment of EVPN in a lab environment. After deployment, I want to run validations to make sure my intent is being met. Lastly, […]
The post Arista BGP EVPN – Ansible Lab appeared first on Overlaid.
This is a follow-up to my previous article, Arista BGP EVPN Overiew and Concepts. In the previous article, I discussed some terminologies and behavior of EVPN and the reason why EVPN is valuable in Data Center and Campus networks. Since then, I’ve learned how valuable it is in Service Provider networks as well, but I’ll […]
The post Arista BGP EVPN – Configuration Example appeared first on Overlaid.
Whether you’re starting out on a fresh playing field or diving into a mud pool of decades-old complexity, designing and deploying a new or modernized data center is a rewarding endeavor; not just for the engineers and architects, but also for the businesses that reap the benefits of agility, scalability, and performance that come along with it.
And the first step on that road is to talk. The initial conversations with thought leaders, business strategists, and technical architects are the most pivotal in the discovery phase of any large project. It is at this phase that the box is forming, and questions must be asked outside of it to shape its dimensions. To transform the network, you must be prepared to ask challenging questions that drive conversations around open networking, automation, modularity, scalability, segmentation and re-usability. Before vendor selection, it is essential to compile a list of business and technical requirements founded upon a set of guiding principles.
Here are seven to keep in your pocket:
1. The network architecture should use standards-based protocols and services
2. The network should be serviceable without downtime
3. The network architecture should promote automation
4. The network should be consumable
5. Physical boundaries Continue reading
Minimalism, as a current concept, is not just about owning fewer things, or eliminating distractions, or consuming only specific coffees sold in unlabeled packaging at chairless coffee shops. Minimalism is a philosophical force and practical approach to life, that when applied correctly, can bring peace, happiness, and enrichment to your way of living. How do these core virtues of minimalism apply to network design? Read on. (And don’t worry, you can keep all of your stuff, your color TV and cell phones, and your roomy house, too – we’re just talking about networks here.)
Joshua Fields Millburn and Ryan Nicodemus, who founded theminimalists.com, sacrificed their former careers to share the concept of minimalism all over the globe, helping more than 20 million people live more meaningful lives. They’ve grounded the concepts of minimalism into a practical and elegant foundation that fits nicely in a modern society. They defined what many believe to be the core virtues of minimalism, ideas to internalize on your journey through life. When it comes to network design, here are five core virtues that prove to be incredibly valuable:
• Reclaim your time
• Create more, consume less
• Contribute beyond yourself
• Experience Continue reading
Introduction Traditionally, Data Centers used lots of Layer 2 links that spanned entire racks, rows, cages, floors, for as far as the eye could see. These large L2 domains were not ideal for a data center, due to the slow convergence, unnecessary broadcasts, and difficulty in administering. To optimize the data center network, we needed […]
The post Arista BGP EVPN – Overview and Concepts appeared first on Overlaid.
TREZOR is a hard wallet for securely storing crypto assets such as Bitcoin, Ethereum, and Litecoin. Protection mechanisms like a mnemonic recovery seed, PIN, and encryption passphrase safeguard your assets (private keys) by requiring your physical interaction in order to make transactions. For those crypto noobies, I think it’s easiest to describe the TREZOR functionality […]
The post Securing Bitcoins with TREZOR appeared first on Overlaid.
A colleague recently asked me if SD-WAN could be leveraged to expedite network integration as a result of a merger or acquisition. His thoughts were that this could potentially provide a means to securely integration networks in a short amount of time. At first I thought this made no sense — SD-WAN is not related to this challenge […]
The post Leveraging SD-WAN for Mergers & Acquisitions appeared first on Overlaid.
I recently ran into a slight bump when deploying the Cisco Cloud Services Router 1000v (CSR) on ESXi vSphere 6.5. The error message I received when trying to deploy the CSR OVA was: VALUE_ILLEGAL: Value “VMXNET3 virtio” of ResourceSubType element not found in [E1000, VmxNet2, VmxNet3]. I Googled this message and found nothing. Great, well […]
The post Issue deploying CSR on ESXi vSphere 6.5 appeared first on Overlaid.
It’s official – I passed the ONF Certified SDN Associate exam. I’m OCSA #SDN10356! If you’re interested in obtaining this certificate, I recommend you read through my short blog series covering the resources necessary on the blueprint. ONF Certified SDN Associate (OCSA) – Part 1 ONF Certified SDN Associate (OCSA) – Part 2 ONF Certified […]
The post OCSA Passed! appeared first on Overlaid.
The OCSA exam tests your understanding of components in an SDN framework, your ability to articulate the fundamental workings of networking and the OpenFlow protocol, as well as your knowledge of vendors, solutions and projects available in the SDN landscape. This is the last part in a series of posts that review the blueprint for […]
The post ONF Certified SDN Associate (OCSA) – Part 5 appeared first on Overlaid.