Most people regard tech professionals as dull people they don’t want to get stuck with at a dinner party, but if you’ve worked in tech for any period of time, then you have likely encou… | Continue reading
Some bash options are well known, and well-used. For example, many people put set -o xtrace at the top of their scripts to debug them, set -o errexit to exit on error, or set -o errunset to exit if… | Continue reading
Then… If, like me, you’re over 40 and work in IT, you’ll probably remember a time when everyone used Windows, and a small but growing proportion of people were wasting their lives… | Continue reading
This post is adapted from an advanced chapter of Learn Git the Hard Way. Each section is self-contained, and should be typed out by hand to ensure the concepts are embedded in your mind and to forc… | Continue reading
What is nmap? nmap is a network exploration tool and security / port scanner. If you’ve heard of it, and you’re like me, you’ve most likely used it like this: nmap 127.0.0.… | Continue reading
Git can be utterly bewildering to someone who uses it casually, or is not interested in things like directed acyclic graphs. For such users, the best thing you can do is buy my book (free sample av… | Continue reading
Culture – Be Specific! People often talk about culture being the barrier to adoption of DevOps, but they are rarely specific about this. This was succinctly put by Charity Majors here: What t… | Continue reading
Culture – Be Specific! People often talk about culture being the barrier to adoption of DevOps, but they are rarely specific about this. This was succinctly put by Charity Majors here: What t… | Continue reading
Here are some tips that might help you be more productive with bash. 1) ^x^y^ A gem I use all the time. Ever typed anything like this? $ grp somestring somefile -bash: grp: command not found Sigh. … | Continue reading
In this article I’m going to give you a hands-on introduction to standard bash debugging techniques. In addition, you’ll learn some techniques to make your bash scripts more robust to f… | Continue reading
tl;dr In this article I want to explain a few things about enterprises and their software, based on my experiences, and also describe what things need to be in place to make change come abo… | Continue reading
In Anatomy of a Linux DNS Lookup – Part I, Part II, and Part III I covered: nsswitch /etc/hosts /etc/resolv.conf ping vs host style lookups systemd and its networking service ifup and ifdown dhclie… | Continue reading
In Anatomy of a Linux DNS Lookup – Part I I covered: nsswitch /etc/hosts /etc/resolv.conf ping vs host style lookups and in Anatomy of a Linux DNS Lookup – Part II I covered: systemd and its networ… | Continue reading
In Anatomy of a Linux DNS Lookup – Part I I covered: nsswitch /etc/hosts /etc/resolv.conf ping vs host style lookups and determined that most programs reference /etc/resolv.conf along the wa… | Continue reading
Since I work a lot with clustered VMs, I’ve ended up spending a lot of time trying to figure out how DNS lookups work. I applied ‘fixes’ to my problems from StackOverflow without … | Continue reading
Here it is (base64-encoded): H4sICIa2A1sCA2IA7Vrrbts2FFYL7M9+7QUGGNyfDYhtkuJFFLAhWZOhBYJmaLMOWBAEFC+xVlkyJLpYEBjdY+0l+k6jfGvqtkEWp2qD8TMg8vAqnsNzDg9lQhhmEjHDhY4zgWJBBUQJ5ZnCGAubMUQMyhJqoRRMJxYbo7Q2… | Continue reading
Autotrace is a tool that allows you to debug a process and: View the output of multiple debug commands at once Record this output for others to review Replay the output All of this is done in a sin… | Continue reading
Punk Rock Git? I’ve spent the last couple of years teaching Git, mostly to users that I like to call ‘punk rock’ Git users. They have three commands, and they can get by with them… | Continue reading
gVisor Someone pointed me at this press release from Google announcing a Docker / container sandbox for Linux. I was intrigued enough to write a ‘quick look’ article on it here W… | Continue reading
Due to a change of job I’ve recently had to teach myself about networking. RFCs had always been a bit of a mystery to me but since they came up over and over again when reading about network … | Continue reading
I work at a very ‘locked-down’ enterprise, where direct access to Docker is effectively verboten. This, fundamentally, is because access to Docker is effectively giving users root. From… | Continue reading