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.

2 ways to create users with Ansible

In the realm of IT automation, Ansible has emerged as a powerful tool for streamlining various administrative tasks. Among these tasks, user management stands out as a common and often repetitive process. Ansible provides two primary approaches for creating users:…

10 Underrated Linux Commands That Deserve More Attention

In recent months, I’ve encountered numerous articles with titles such as “20 Linux Commands You Should Know” or “Linux Survival Guide.” However, I’ve observed that most of these articles target beginners and cover basic commands like ls or echo. Considering…

3 ways to fix useradd: Permission denied in Linux

The “useradd: Permission denied” error typically occurs when the user executing the useradd command does not have the necessary permissions to create a new user account. To fix this error, you can try the following solutions: Switch to the root…

2 ways to check if user account is locked or not in Linux

understanding user password authentication in Linux The user authentication process in Linux typically involves validating the entered credentials against the stored user information in the /etc/passwd and /etc/shadow files. When a user attempts to log in, they provide a username…

understanding network CIDR /24

CIDR stands for Classless Inter-Domain Routing. It is a method used for allocating and routing IP addresses on the Internet. A /24 CIDR, such as 192.168.1.0/24, indicates that the first 24 bits are the network part of the address, leaving…

2 ways to list all users in Linux

Linux is designed to be a multi-user operating system, allowing multiple users to access and utilize the system concurrently. To effectively list the users on a Linux system, two powerful methods come into play: using the “cat /etc/passwd” command and…