David Cao

David Cao

David is a Cloud & DevOps Enthusiast. He has years of experience as a Linux engineer. He had working experience in AMD, EMC. He likes Linux, Python, bash, and more. He is a technical blogger and a Software Engineer. He enjoys sharing his learning and contributing to open-source.

How To Change Hostname in Ubuntu

Setting a unique and descriptive identity for your server is one of the first steps in effective system administration. Without a correctly configured hostname, automated scripts and monitoring tools may fail to identify your machine, leading to confusion in logs…

Understanding the Linux Sticky Bit Permission

In a standard Linux environment, directory permissions can sometimes be counterintuitive. By default, any user with write access to a directory has the power to delete or rename any file within that directory, regardless of who owns the file or…

How to Find and Analyze Hot Data in PostgreSQL

Imagine you are managing a multi-terabyte database, but only a fraction of that data is actually powering your application’s real-time performance. Without knowing which tables and indexes are “hot”—meaning frequently accessed and ideally stored in memory—you are essentially flying blind…

How to Use fapolicyd in RHEL (Step-by-Step Guide)

If you are managing a Red Hat Enterprise Linux (RHEL) server, you likely face the challenge of ensuring only trusted software runs on your system. You might find yourself in a scenario where a user accidentally downloads an untrusted script…