How to record statistics about a Linux machine’s uptime

Posted on in Categories Command Line Hacks, Hardware last updated November 15, 2017

Linux/Unix sysadmins have a weird obsession with server uptime. There is a xkcd comic devoted to this subject where a good sysadmin is an unstoppable force that it stands between the forces of darkness and your cat blog’s servers.
Fig.01: Devotion to Duty
One can tell how long the Linux system has been running using the uptime command or w command or top command. I can get a report of the historical and statistical running time of the system, keeping it between restarts using tuptime tool. Like uptime command but with the more impressive output. Recently I discovered another tool called uptimed that records statistics about a machine’s uptime. Let us see how to get uptime record statistics using uptimed and uprecords on Linux operating system.

Improve your bash/sh shell script with ShellCheck lint script analysis tool

Posted on in Categories Command Line Hacks, Howto, Programming last updated November 9, 2017

ShellCheck is a static analysis tool for shell scripts. One can use it to finds bugs in your shell scripts. It is written in Haskell. You can find warnings and suggestions for bash/sh shell scripts with this tool. Let us see how to install and use ShellCheck on a Linux or Unix-like system to enhance your shell scripts, avoid errors and productivity.

How to colorizing cat command output or files using ccat app on Linux or Unix system

Posted on in Categories Command Line Hacks, Howto last updated August 30, 2017

The cat command (short for concatenate) is one of the most frequently used flexible commands on Linux, Apple MacOS X, *BSD (FreeBSD / OpenBSD / NetBSD), Unix-like operating systems. It is useful to display text files on screen, copy text files, combine text files, create new text files and more. If you cat command with colours, try ccat app.

I put a cronjob in /etc/cron.{hourly,daily,weekly,monthly} and it does not run and how can I troubleshoot it?

Posted on in Categories Cloud Computing, Howto, Open Source, Web Developer last updated August 27, 2017

Recently I created a simple shell script called in /root/scripts directory to just backup MySQL database and dumped it to /nfs/mysql/ directory. I put a file (more like used the ln command to create a soft link ) in /etc/cron.hourly/ and it doesn’t run. There was no error in systemd log or cron log. Why is my cron job was not working, and here is how I troubleshoot it.

Linux/Unix desktop fun: Bastet Tetris(r) clone with block-choosing AI for console

Posted on in Categories Linux Games, Open Source last updated August 18, 2017

Xkcd - hell
Do you love the puzzle and Linux/Unix-like system? Command line? Try ncurses based Tetris clone which is harder than every other Tetris out there. From the project home page:

Have you ever thought Tetris(R) was evil because it wouldn’t send you that straight “I” brick you needed in order to clear four rows at the same time? Well Tetris(R) probably isn’t evil, but Bastet certainly is. >:-) Bastet stands for “bastard tetris”, and is a simple ncurses-based Tetris(R) clone for Linux. Unlike normal Tetris(R), however, Bastet does not choose your next brick at random. Instead, Bastet uses a special algorithm designed to choose the worst brick possible. As you can imagine, playing Bastet can be a very frustrating experience!