January 31, 2020 update: No, you're not crazy. Cisco changed the exam number from 300-401 to 350-401.

For your convenience, I've put together the following list of my courses that cover the new CCNP ENCOR exam. By watching and following along with the hands-on demos in these courses, you can't go wrong.

Routing …

Despite the proliferation and availability of information, good information is hard to come by. Finding the right data is often a matter of quickly dismissing sources of bad data, allowing the cream to rise to the top. To speed up this process, I've created the following list of sources that I've found to consistently …

You took one of the Cisco CCNP exams. You went to the exam center, sat down, and started the exam. About 2 hours later, you saw the dreaded news appear on the screen:

You didn’t pass.

I’ve failed certification exams in the past, so I can relate to the facepalm-worthy feeling you get when you realize you dropped a …

Note: This is a previously unpublished post I wrote in early 2020. I'm posting it now (late 2022) as a reminder that critical thinking based on existing scientific knowledge turned out to be right, while the "experts" were wrong. Your worldview matters. The "experts'" by and large operate on an …

As an AWS customer, you share responsibility with AWS for the security of your data the cloud. There’s a mantra: AWS handles the security of the cloud, but you handle security in the cloud.

But it turns out that’s not quite true. For more, check out my guide Operating within the AWS Shared Responsibility Model.

As someone who works in IT, I hear and read a lot of comments about science. One common but unfortunate claim is that “science is not about finding truth.” While I won’t get into the underlying philosophical reasons behind this claim, I do want to at least respond to it on its face.

Etymology of the word “science”

The …