Recently, I was reading an article on the recently discovered hacker group dubbed the Equation Group[1], I stumbled across an interesting concept: encrypted malware payloads. Most server admins will inevitably have the experience of dealing with a comprised system, especially if you host sites running WordPress[2][3], IPB[4], vBulletin[5], Drupal[6], or a host of other systems […]
Author: Brandon Wamboldt
Basics Of Scaling: Cache Everything
I do a lot of work on websites that needs to scale fairly well, but I tend to use that mentality for every project. Part of scaling is performance, and the better your app performs (e.g. the more requests per second it can handle) the cheaper it is. One very easy way to improve your […]
WIP: Circuit Sandbox
I’ve been working on an HTML5 Canvas game recently, designed to be an educational sandbox that allows people to create logic gates and build circuits. You’ll start with just transistors and wires, and have to build nand, nor, and, or, xor, not, etc logic gates, which you can then re-use to build more complex circuits […]
Understanding the PHP-FPM status page
PHP-FPM has a very useful feature that allows you to setup a status page to view that status of a PHP-FPM pool, configurable using the option pm.status_path. Most people who have worked with PHP-FPM have probably heard of this setting, and maybe even used it (some tools such as Munin require it for metrics). Here […]
Rant: Constants can’t be mutable
I’ve been working with Ruby lately, and a few people have told me that Ruby has constants, but they are mutable. Recently, I’ve been reading a new book on Ruby, and read the following passage: A lot of other places mirror this (e.g. rubylearning.com). You cannot have constants if they are mutable. Mutable constants are just […]
If you use bash colors, check for a tty first!
Most of the command line programs I write use ANSI escape codes to output colored text (along with bold/underlined text). I find this makes the programs a lot easier to understand at a glance. For example, my test runners will output success in green, skipped in yellow, and failure in red. I can very quickly […]
How Linux pipes work under the hood
Piping is one of the core concepts of Linux & Unix based operating systems. Pipes allow you to chain together commands in a very elegant way, passing output from one program to the input of another to get a desired end result. Here’s a simple example of piping: ls -la | sort | less The […]
Analysis of a WordPress plugin exploit
This morning, I was reading ArsTechnica like I do every morning, and saw an article about how yet another popular WordPress plugin was found to have a remote execution vulnerability. The comments on the article were predictably bad and misinformed, so I decided to look into the security fix and see what caused the original […]
Understanding how Linux creates processes
A friend recently read my post on how bash redirection works, but didn’t quite understand my explanation of how bash launches another process and sets stdin/stdout/stderr, so this is a follow up post. Linux creates every process using the fork(2) or clone(2) syscalls. The only way to create a process is to fork your current […]
So what is /proc anyways?
I’ve been using Linux for years, but I’ve never really known was /proc was or why certain commands used it. I’m not sure why I’ve never looked it up in the past, but I recently did and I thought I’d share. /proc isn’t a “real” directory, in the sense that it doesn’t exist on disk. […]