Month: <span>October 2026</span>
DevStack local.conf Explained: Configuration Options and Examples
Every time you deploy DevStack, the file you edit most is local.conf. It is the configuration file that tells stack.sh what passwords…
How to Install DevStack on Ubuntu 24.04: Step-by-Step Guide
Installing DevStack on a clean Ubuntu 24.04 LTS virtual machine gives you a disposable OpenStack cloud for testing or learning. The process…
du and df: Find What’s Filling Your Disk on Linux
When a Linux disk fills up, df says it is full but du cannot find the files. This guide shows how to…
DevStack vs OpenStack: The Key Differences Explained
The question that brings most people here is simple: should I use DevStack, or should I deploy OpenStack? The short answer: DevStack…
What Is DevStack? A Beginner’s Guide to OpenStack Development Environments
DevStack is a set of extensible shell scripts that deploy a complete OpenStack cloud on a single machine for development, testing, and…
AI Agents for Ubuntu 24.04 Server Security Auditing: A Practical Guide
AI agents can help audit Ubuntu 24.04 servers for security issues — file permissions, SSH configuration, exposed services, outdated packages, and suspicious…
grep and sed: Search and Replace Text From the Command Line
You have a configuration file with a hundred lines and you need to change one IP address. Or a log file with…
SSH Key Permissions Too Open: Why SSH Rejects Your Key
You run ssh user@server and instead of a login prompt, you see a block of red text ending in “Permission denied (publickey).”…
The Linux find Command: Find Files by Name, Size, Time, and Permissions
You need to find a file, but you only remember part of its name, or you need to find every file larger…
Reading TLS Certificates with openssl
Certificate problems are confusing for a specific reason: the certificate is almost never the thing that is wrong, and openssl will happily…