Java (JRE/JDK) – Check version installed

The Java development kit (JDK) contains tools for Java development, and the Java Runtime Environment (JRE) contains a JVM to convert byte code .class to machine code, and execute it, in short, the JRE runs Java program. In this this article we will see different methods to check which version is installed on a Linux/Windows system. Read More …

Linux – Methods to repeat a command every X seconds

A Linux system administrator needs to know, sometimes for specific type of tasks, how to run or repeat a Linux command every X seconds. You may need to run a command repeatedly in a certain period of time. Using simple cron commands, for example, such tasks can be easily completed. But cron is not the only tool that we can use to do that. Read More …

Linux – Mount ext4 USB flash drive to Raspberry Pi [New Question]

A quick question, answered on Heelpbook, about “Mount ext4 USB flash drive to Raspberry Pi”, especially useful when attaching external storage, HDDs or SSDs, to a Raspberry PI (or any Linux-based system) to expand storage for applications and services. Read More …

Run node.js app as a daemon process (Linux)

We have a node.js server/app and we start it by using npm start & (background mode) command through Putty. But the problem is that if we close Putty (or any other SSH client) the server will be stopped after sometime. We can use pm2 of forever process managers to address/fix this scenario. Read More …

Linux – The cp command

One of the most common command to use (and need to be used) on Linux systems, especially when working on CLI only systems (with no GUI installed), is the cp (copy) command. The following section of this article will show several common and advanced ways to use cp command on Linux systems on files and folders.
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