Modern RHEL-based systems (EL9+) ship with dnf as the package manager. Most additional software you’ll need comes from well-maintained third-party repositories rather than compiling from source. This guide covers the essential ones and how to use them safely. EPEL (Extra Packages for Enterprise Linux) EPEL is the go-to third-party repository for RHEL-based systems. It provides…
Systemd replaced traditional init on most modern Linux distributions, shifting terminology from “runlevels” to “targets.” If you’re migrating from older systems, here’s the mapping: Runlevel Systemd Target Purpose 0 poweroff.target Shutdown 1 rescue.target Single-user mode 2, 3, 4 multi-user.target Multi-user, no GUI 5 graphical.target Multi-user with GUI 6 reboot.target Reboot The two targets you’ll use…
When you dock a laptop with an external USB keyboard, the built-in keyboard becomes a nuisance—it’s too easy to brush keys while typing and trigger unwanted input. Rather than disabling the keyboard at the BIOS level or physically disconnecting it, you can use the xinput tool to disable and re-enable it from within your Linux…
NetworkManager is the default network management tool on modern Fedora, RHEL, and CentOS systems. You can configure static IPs either through the CLI or by editing configuration files directly. This guide covers both approaches for Fedora 41+ and RHEL 9+. Identify your network interface Start by listing all available network interfaces: ip link show or…
Running commands across multiple servers is fundamental to cluster management and infrastructure automation. While orchestration tools like Ansible and Terraform dominate modern deployments, sometimes you need lightweight solutions that work without dependencies—or you’re already invested in SSH-based infrastructure. When managing clusters, you typically work in two modes: serial execution (one node at a time) and…
Before writing code, get comfortable with fundamental Linux commands. You’ll use these daily: File operations: ls, cd, cat, less Text search: grep, ripgrep (rg) Remote access: ssh, scp, rsync Session management: tmux or screen for persistent terminal sessions Shell: bash (default on most distributions), though zsh and fish are popular alternatives Start with built-in documentation….
Install AWS CLI v2 through your system’s package manager for production deployments. On Debian/Ubuntu: sudo apt-get update sudo apt-get install awscli On RHEL/CentOS/Fedora: sudo dnf install awscli Or use the official installer directly: curl “https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip” -o “awscli-v2.zip” unzip awscli-v2.zip sudo ./aws/install Verify installation: aws –version Configure AWS CLI credentials Set up credentials interactively: aws configure…
Flash is dead on the web. Adobe ended support on December 31, 2020, and all modern browsers removed plugin support years ago. If you need to view Flash content in 2026, you have two practical options: the Ruffle emulator or running legacy applications in isolated environments. Why Fresh Player Plugin and PPAPI Don’t Work Anymore…
Watching for filesystem changes and triggering actions is essential for development workflows—recompiling after source edits, restarting services when configs update, or running tests during coding. Linux’s inotify subsystem provides kernel-level file monitoring, and inotifywait makes it accessible from the command line. Installation Install inotify-tools on your system: Fedora/RHEL/CentOS: sudo dnf install inotify-tools Debian/Ubuntu: sudo apt…
Configuring an HP all-in-one printer’s scanner on Linux requires HPLIP (HP Linux Imaging and Printing) for device support and SANE (Scanner Access Now Easy) for scanning functionality. The main gotcha is that a working printer doesn’t guarantee a working scanner — they use different subsystems and need separate configuration. Installing Required Packages Start by installing…
When you repurpose disks from one RAID array to another system, Linux keeps the old RAID metadata intact as a safety measure. This prevents accidental data corruption, but it also blocks you from reusing the disk until the signatures are cleared. RAID metadata isn’t stored in one place — it’s scattered across the disk by…
GRUB2 configuration needs to be regenerated when you modify boot parameters, install new kernels, or adjust default boot entries. The process varies slightly between BIOS and UEFI systems, and between distributions, but follows a consistent pattern once you understand your system layout. Check Your System Firmware Type Before regenerating config, identify whether your system uses…
You’re using a Linux-based OS right now, either directly or indirectly. But what do you actually call it? The naming question matters more than it seems — different distributions frame themselves differently, and understanding the terminology affects how you talk about infrastructure, apply for jobs, and read documentation. How Major Distributions Identify Themselves Red Hat…
A toggle-on-demand terminal you can summon and hide with a single keystroke is useful for quick commands without cluttering your workspace. This guide walks you through creating one using GNOME Terminal and basic shell scripting. Prerequisites You need xdotool and wmctrl installed to manipulate windows: # Debian/Ubuntu sudo apt install xdotool wmctrl # Fedora sudo…
Chrome on Linux uses NSS (Network Security Services) for certificate management. Install the certutil utility from your distribution: Debian/Ubuntu/Linux Mint: sudo apt install libnss3-tools CentOS/Fedora/RHEL: sudo dnf install nss-tools Arch Linux: sudo pacman -S nss Extract and Import the Certificate The most reliable approach is to extract the certificate directly from the server and import…
GPT (GUID Partition Table) is required for disks larger than 2TB. The older MBR format maxes out at 2.2TB due to 32-bit sector addressing. Tools like fdisk will refuse to work properly with large drives and recommend switching to GPT. While parted has a steeper learning curve than some alternatives, it’s the standard for GPT…
The Linux kernel handles video mode configuration through bootloader parameters and kernel graphics drivers. Modern UEFI systems use Kernel Mode Setting (KMS) automatically, but you can override modes when needed. Legacy BIOS systems still use older mechanisms if you’re maintaining older hardware. UEFI Systems: Modern Video Mode Configuration On UEFI systems with GRUB2, add video…
Hadoop 2.x reached end-of-life in 2016. This guide covers setup for learning purposes and legacy system maintenance only. For production deployments, use Hadoop 3.x or later, which includes performance improvements, better YARN scheduling, HDFS erasure coding, and improved security. Cloud-managed options like AWS EMR, Google Dataproc, and Azure HDInsight eliminate most operational overhead. This guide…
A file-backed VBD stores the entire VM disk in a single file on the Dom0 filesystem. This approach works well for testing and development, though LVM-backed or disk-backed storage provides better performance for production workloads. Create a working directory and a 20GB sparse file-backed VBD: mkdir -p /home/xen/f41install cd /home/xen/f41install dd if=/dev/zero of=./vmdisk0 bs=1k seek=20480k…
Xen remains a production-grade hypervisor used by major cloud providers like AWS and Citrix, though KVM has become the default for most Linux distributions. This guide covers setting up Xen Domain-0 (the privileged management domain) on modern Fedora systems. Installing Xen Packages Install the required Xen packages: sudo dnf install xen xen-libs xen-runtime xen-dom0-tools Modern…