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 [nixcmd name="cat"] (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 backup.sh 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!

Increase your Linux server Internet speed with TCP BBR congestion control

Posted on in Categories Cloud Computing last updated July 22, 2017

I recently read that TCP BBR has significantly increased throughput and reduced latency for connections on Google’s internal backbone networks and google.com and YouTube Web servers throughput by 4 percent on average globally – and by more than 14 percent in some countries. The TCP BBR patch needs to be applied to the Linux kernel. The first public release of BBR was here, in September 2016. The patch is available to any one to download and install. Another option is using Google Cloud Platform (GCP). GCP by default turned on to use a cutting-edge new congestion control algorithm named TCP BBR.

Linux security alert: Bug in sudo’s get_process_ttyname() [ CVE-2017-1000367 ]

Posted on in Categories Security last updated May 31, 2017

CVE-2017-1000367
There is a serious vulnerability in sudo command that grants root access to anyone with a shell account. It works on SELinux enabled systems such as CentOS/RHEL and others too. A local user with privileges to execute commands via sudo could use this flaw to escalate their privileges to root. Patch your system as soon as possible.

Intel Euclid: Ideal platform for Robotics and Ubuntu Linux powers it

Posted on in Categories Hardware last updated May 23, 2017

Intel announced Euclid development kit for robotics. It is Ubuntu Linux 16.04 based system. One can run, monitor and manage their robotics apps with the web interface. The software works with any ROS-based (Robotics Operating System) robot such as Arduino to build sensing capabilities in your project. You can use sensors and cameras to control a robot.