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April 17, 2019 – 4:51 pm

Just a quick collection of notes on – rather than a definitive guide to – setting up an SSH chroot jail on RHEL 6. The same should work on RHEL 7 and unrelated flavors. For …

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Creating a Chroot Jail for SSH Access

April 17, 2019 – 4:51 pm
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Just a quick collection of notes on – rather than a definitive guide to – setting up an SSH chroot jail on RHEL 6. The same should work on RHEL 7 and unrelated flavors. For …

Encrypting Log Data During Log Rotation

April 9, 2019 – 4:12 pm
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Most log files do not contain personally-identifiable information or other sensitive data. And even if they do, encryption of all personal data is not mandatory under GDPR. Still, on occasion, for testing and troubleshooting purposes …

DevOps Obfuscation

April 6, 2019 – 4:10 pm
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Some years ago I’ve been reading “DevOps in Straight English” by Magnus Hedemark [efn_note]“DevOps in Straight English – Part 1 of 2 – Enter the Buzzword.” RHD Blog, 20 Apr. 2018, developers.redhat.com/blog/2014/01/15/devops-in-straight-english-part-1-of-2/. [/efn_note] and encountered the …

Gnuplot with Bash

April 2, 2019 – 4:08 pm
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OK, so both of these things have been around forever and will be around long after we’re gone. It’s worth your time to learn how to use the to together.

File Compression Testing

January 27, 2019 – 5:29 pm
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For some reason I haven’t used zip much on Linux, sticking to the standard tar/gzip combo. But zip seems to be a viable alternative. While not as space-efficient, it is definitely faster; syntax is simple; …

Killing Process Network Access

January 27, 2019 – 4:45 pm
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Imagine this scenario: a particular process on your server is connecting to a host outside your internal network and you don’t like that. On the other hand, you can’t just kill that process because you need it.

Installing t CLI power tool for Twitter

January 21, 2019 – 4:41 pm
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The ‘t’ is an excellent Ruby-based CLI utility for interacting with the Twitter API written by Erik Berlin. This is certainly not the only such tool available, but, in my estimation, it is the most full-featured and expertly-written. No amateur-hour coding here.

Keeping Abreast with Filesystem Changes

January 17, 2019 – 4:39 pm
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The inotify is a Linux kernel sybsystem for notifying user-space applications of filesystem changes. I always thought this exceptionally handy utility was under-appreciated or at least underutilized.

Inventory Network Services with Nmap

January 14, 2019 – 4:32 pm
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With the growing number of network-enabled devices in your home, meaningful security becomes elusive. The first step to addressing the situation is knowing what you have. A few examples below use the nmap utility to scan your local network and detect active devices and services.

Automating Web Page Screenshots

January 9, 2019 – 4:22 pm
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Automatic Web page screenshots are commonly used for various monitoring tasks, such as detecting copyright infringement, website defacement, and other legal and security matters. Automatic screenshotting can also be a useful tool for researchers, developers, and journalists. There are free and open-source tools out there that can help you automate the task of creating Web page screenshots.

The Future of Spaghetti Code

August 18, 2018 – 4:20 pm
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In his new book “The Future of Work: Robotics, AI, and Automation”1, Darrell West of the Brookings Institution makes some very extravagant predictions. Here’s a short but entirely sufficient summary from the book’s presentation by …

AWS CLI Cheat Sheet

August 14, 2018 – 4:18 pm
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The installation and configuration process for AWS CLI is fairly simple. The package itself is installed with pip (yum -y install python-pip):

Copying X11 Magic Cookies

August 10, 2018 – 4:17 pm
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I rarely use GUIs, but when I do, it’s from CLI and every time I run into the annoying MIT-MAGIC-COOKIE-1 data did not match error. It’s easy to fix, but it happens to me so …

Verify Network Port Access

August 8, 2018 – 4:15 pm
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There are several tools you can use to verify access to a remote network port: nc, tcping, telnet. Unfortunately, nc from the netcat package has been replaced by the one from nmap, which lacks the -z option, making …

Late Night Rant: Agile

August 5, 2018 – 4:11 pm
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CollabNet VersionOne has released it’s 12th annual “State of Agile” report. The survey involved more than 1,400 software professionals in various roles and industries over the fourth quarter of 2017.

Only 12% responded that their organizations …

Document Conversion with Unoconv

August 4, 2018 – 4:08 pm
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The other day I ran into the “Flexible Import/Export” article by Bruce Byfield in the March 2018 issue of Linux Pro Magazine and thought it could use some more detail. So here’s some more detail.

How Not to Prepare for a SysAdmin Interview

August 2, 2018 – 4:06 pm
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The Linux Foundation just gave birth to seven supposedly interesting tips on how to prepare for a Linux SysAdmin job interview. Unfortunately, the research behind all this probably excellent advice was based on interviewing hiring …

Automating Web Page Screenshots

July 13, 2018 – 2:25 pm
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Automatic Web page screenshots are commonly used for various monitoring tasks, such as detecting copyright infringement, website defacement, and other legal and security matters. Automatic screenshotting can also be a useful tool for researchers, developers, …

Encrypted Volumes and Portable Apps

February 25, 2018 – 3:08 pm
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This is a description of an uncomplicated setup for an encrypted volume and portable applications for a Windows laptop consisting of a USB3 storage device, VeraCrypt OSS OTFE, a hardware password wallet, and portableapps.com software.

Detect SSL Certificate Injection

February 21, 2018 – 3:05 pm
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When the SSL Digital Certificate is intercepted and replaced by a device between your browser and the Web site, we call it certificate injection. This method is more commonly used not by hackers, but by …

SSL For Self-Hosted WordPress

February 17, 2018 – 3:05 pm
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Just some notes for setting up SSL with your self-hosted WordPress installation. Just got around to doing this the other day. Yeah, I know, about time…

Obfuscating Passwords in Shell Scripts

December 17, 2017 – 9:41 am
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At the risk of repeating myself, I must say that this article is about obfuscating passwords – rendering obscure, unclear, or unintelligible – not hiding them. This can still be useful.