System Code Geeks Operating System Developers Resource Center

Here at System Code Geeks we know how much you love books about system administration; we are geeks ourselves. After all, a geek that respects himself should always have his face in a book, he has to keep up with the latest technologies and developments. For this reason, we have decided to distribute 6 of our books for free. You ...

Have you ever deleted any important files by mistake? Who doesn’t! Okay, but can I recover them? In this post, you will learn how to recover deleted files on Linux using various programs on different file systems. You will see how to recover deleted files from SD cards, HDDs, and deleted partitions on different Linux file systems such as EXT3, ...

Recently we experienced an interesting production problem. This application was running on multiple AWS EC2 instances behind Elastic Load Balancer. The application was running on GNU/Linux OS, Java 8, Tomcat 8 application server. All of sudden one of the application instances became unresponsive. All other application instances were handling the traffic properly. Whenever the HTTP request was sent to this ...

Driving home from a long day of work, I see the beautiful sky and so to not miss the beauty, I decided to pull over to take this picture. But then coming home, I was reminded of today’s challenges and I felt that it’s best to document my findings for posterity and to share it with the rest of the ...

Thanks to Linux, we have access to many tools that facilitate networking administration & diagnostics. In this sense, the Linux ping command is one of the most useful tools for sysadmins and network administrators. Its basic function is to determine if one host of the network is reachable or not. However, in this post, we will address other more advanced capabilities ...

Every organization needs to collect logs from multiple sources in order to put them in either a log collector or SIEM (or a dedicated audit trail solution). And there are two options for that – using an agent and agentless. Using an agent is easy – you install a piece of software on each machine that generates logs and it ...

In this post, we will cover many aspects of MySQL on Linux. First of all, how to install it, how to perform basic CRUD operations, how to import & export data, play with the MySQL engine itself such as setting the root user password and much more. MySQL is one of the most popular relational databases engines in the world. ...

Number 4 in my Che series… a quick guide for using Minishift, in order to test drive Che 7 or Red Hat CodeReady Workspaces. If you’re not running Windows as your host OS, your mileage may vary in terms of memory requirements and preferred virtual machine driver, but the suggestions below should work on most OSes… even the one with ...

Number 5: deploying Che 7 behind a firewall (air gap environment) using chectl –che-operator-cr-yaml=… Deploying Che 7 with custom images Unlike  Deploying Che 7 to Minishift 1.34+, this doc will explain how to do an Eclipse Che 7 deployment with a custom resource yaml file to override the images used in the deployment. This process can be used for many things, ...

For pedantic people like myself, who like to keep their Desktop tidy, I came across this tip to save screenshots to a different location automatically. Create a folder (mine is called Screenshots)Open a Terminal windowType the following: defaults write com.apple.screencapture locationDrag and drop the folder into terminal. You’ll end up something like the following: defaults write com.apple.screencapture location /Users/pkua/Desktop/ScreenshotsHit enter! ...