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When a kernel panic occurs on a remote Linux server, manual intervention via SSH becomes impossible. The kernel can be configured to automatically reboot after a panic, allowing the system to recover without human intervention. Enable Kernel Panic Auto-Reboot The kernel.panic parameter controls this behavior. A value of 0 disables auto-reboot; any positive integer specifies…
Rocky Linux 9 can blank the console screen after a period of inactivity, but by default it may not actually power off the display. This is often caused by kernel mode settings or DPMS (Display Power Management Signaling) configuration. Check Current DPMS Status First, verify whether DPMS is enabled on your console: cat /sys/module/kernel/parameters/consoleblank If…
Finding files that match a pattern is straightforward with ls *string* or find . -name ‘*string*’. But excluding files with a certain string in their filename requires a different approach. Using find with negation The most reliable method is find with the ! (or -not) operator: find . -type f ! -name ‘*string*’ This finds…
RPM Fusion provides additional packages not available in standard CentOS, RHEL, and Rocky Linux repositories, including multimedia codecs, drivers, and other proprietary software. This guide covers enabling both the free and nonfree repositories. Prerequisites Root or sudo access CentOS/RHEL/Rocky Linux 9 (or compatible) Active internet connection Enable RPM Fusion The easiest method is using the…
vbetool is a utility for executing real-mode x86 BIOS calls, commonly used for power management and display mode switching on legacy systems. Rocky Linux 9 doesn’t include it in standard repositories, so you’ll need to build it from source. Prerequisites Install the required development tools and dependencies: sudo dnf groupinstall “Development Tools” sudo dnf install…
Converting PPTX presentations to image files on Linux requires a two-step process: first convert to PDF, then rasterize to your target image format. This approach preserves slide layout and fonts better than direct conversion tools. Convert PPTX to PDF Start by converting your PowerPoint file to PDF using LibreOffice: libreoffice –headless –convert-to pdf presentation.pptx The…
Converting between Simplified Chinese (SC) and Traditional Chinese (TC) characters on Linux is straightforward with OpenCC, a mature open-source tool designed specifically for this task. Installing OpenCC Most distributions include OpenCC in their standard repositories: # Debian/Ubuntu sudo apt install opencc # RHEL/CentOS/Fedora sudo dnf install opencc # Arch sudo pacman -S opencc Alternatively, build…
The default dd command can feel sluggish because it uses a small block size (512 bytes) by default. You can dramatically improve throughput by increasing the bs (block size) parameter. Basic optimization Instead of: dd if=/dev/sda2 of=./sda2.bak Use: dd if=/dev/sda2 of=./sda2.bak bs=1M The bs parameter controls how much data dd reads and writes in each…
Listing active services is essential for system monitoring and troubleshooting. Whether you’re investigating a hung process, checking if a daemon started correctly, or auditing what’s actually running on your system, knowing how to query service status quickly saves time. Basic Command The standard way to list running services across all modern Linux distributions is: systemctl…
iptables remains the standard firewall configuration tool on Linux systems, though many distributions now layer it with ufw or firewalld. Understanding the basics helps you troubleshoot, migrate, or work on systems without those abstractions. Understanding iptables Fundamentals iptables operates on three main chains: INPUT: rules for incoming traffic FORWARD: rules for traffic passing through the…
Making firewall rules persistent across system reboots is essential for any production Linux system. While the original iptables-persistent approach works, modern systems typically use ufw (Uncomplicated Firewall) or firewalld, but understanding the underlying iptables mechanism is still valuable for lower-level control. Using iptables-persistent The iptables-persistent package automatically saves and restores your firewall rules during boot….
When managing packages on Ubuntu or Debian systems, knowing what versions are available—and which one will be installed—is essential for dependency management and system stability. The aptitude command provides several ways to inspect package versions. Check all available versions of a package The most straightforward approach is to use the versions subcommand: aptitude versions package-name…
musl libc is a lightweight C library implementation that’s useful for creating statically-linked binaries, containerized applications, and embedded systems. It’s the standard C library in Alpine Linux and increasingly common in production environments. Installation from distribution repositories The simplest approach is installing musl from your distribution’s repositories: sudo apt update sudo apt install musl musl-dev…
When you need to audit disk usage or understand directory structure, counting files in each subdirectory is a common task. This is especially useful when dealing with large directory trees where you need a quick overview of distribution. The Basic Approach The simplest method uses a loop with find and wc: for i in */;…
When you run cat /etc/resolv.conf on a modern Linux system, you’ll often see nameserver 127.0.0.1 or 127.0.1.1 pointing to localhost. This doesn’t mean you’re actually using your ISP’s DNS directly — it usually means your system is running a local DNS stub resolver or caching service like systemd-resolved or dnsmasq. To find out which actual…
Linux Mint’s Cinnamon desktop automatically mounts removable media like USB drives and external hard drives by default. If you prefer manual control over when and how storage devices are mounted, you can disable this behavior through Nemo, the Cinnamon file manager. Disable Auto-Mounting via Nemo Preferences The simplest approach is to configure Nemo’s mounting behavior…
If you need to resize, crop, or annotate images on Linux but GIMP feels like overkill, several lightweight alternatives exist that handle everyday editing tasks efficiently without the complexity. Pinta Pinta is a straightforward drawing and image editor designed for simplicity. It covers basic operations like resizing, cropping, rotating, and adding text annotations without overwhelming…
When managing a Linux system remotely, you sometimes need to terminate all sessions for a specific user—whether they’re logged in locally at the console, via SSH, through X11 forwarding, VNC, or any other method. Here’s how to do it. Quick Answer To terminate all processes for a user named bob: killall -u bob This kills…
Resizing a single image is straightforward, but processing dozens or hundreds requires automation. ImageMagick’s convert command (or the modern magick command) paired with a bash loop is the standard approach for batch image resizing on Linux. Using ImageMagick ImageMagick remains the most reliable tool for this task. Here’s a practical script to resize all images…
GNU Screen’s status bar (called the hardstatus line) displays useful information about your current session—which window you’re on, the time, hostname, and more. It’s especially helpful when you’re running multiple windows and need a quick visual reference without typing commands. Basic Status Bar Setup Add these lines to your ~/.screenrc: hardstatus alwayslastline hardstatus string ‘%{=…