101 Public DNS Servers Sorted by Speed

Posted on March 4


You probably know the popular Google DNS server IP addresses by heart: and Before those were around you might have even used Level3’s and Of course, everyone else uses these too, which means these popular servers are under a pretty heavy load. Fortunately, there are faster public DNS servers out there. […]

Installing PowerShell Core on Amazon Linux

Posted on February 25


In preparation for my latest course in the AWS Networking Deep Dive series, I wanted to install PowerShell Core on an Amazon Linux instance to test out cross-platform compatibility for some scripts. Specifically, I wanted to see if I could use methods in the System.Net.Dns class to perform name resolution. The dnsclient PowerShell module provides […]

Half off Learn Cisco Network Administration in a Month of Lunches

Posted on February 23


Today only! Get half off my book Learn Cisco Network Administration in a Month of Lunches. Just use code dotd022318au at

Is Social Media Bad?

Posted on February 21


Most of us have tossed around the idea of restricting our social media consumption, or even giving it up altogether. It’s not that we don’t like it. We love it, sometimes too much. But inherently, something about social media just seems wrong. But what is it? Social is Not a Neutral Tool People often say […]

Video: How to Subnet in Your Head

Posted on February 9


Learn to subnet in your head in just seconds! This clip is from my Pluralsight course Basic Networking for CCNP Routing and Switching 300-101 ROUTE.