Clear HSTS settings cached in browser (Chrome, Brave, Firefox, Safari, EDGE)

HSTS was created in response to an HTTPS vulnerability that was discovered by computer security researcher Moxie Marlinspike. With HSTS protocol, the website forces the browsers to open the website strictly with HTTPS only. In this article we can see how to clear HSTS entries cached in browsers to get access again to websites that have been refreshed server-side (certificate renewed or CA changed) or for corrupted entries client-side. Read More …

Microsoft Windows – “The specified service has been marked for deletion” error [New Question]

A quick question, answered on Heelpbook, about “Microsoft Windows – “The specified service has been marked for deletion” error”, a scenario that could arise while automating configurations and/or deployments (but also on simple standalone systems) on Windows systems. Read More …

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 …