Set Up an NFS Server Package Installation Install the required packages: dnf install nfs-utils nfs-utils includes both server and client tools. The separate rpcbind package is no longer needed on modern systems — it’s handled as a dependency and runs as part of the NFS service. Configure /etc/exports Edit /etc/exports to define which directories clients…
SSH Key Setup Every user working with Git needs an SSH key pair for authentication. Generate one if you don’t have it: ssh-keygen -t ed25519 -C “your-email@example.com” Ed25519 keys are preferred over RSA for better security and performance. The command creates ~/.ssh/id_ed25519 (private key) and ~/.ssh/id_ed25519.pub (public key). Share the public key with your Git…
Integrating Vim with Thunderbird Thunderbird’s built-in compose window is functional but limited. Using Vim as an external editor gives you the full power of modal editing and your customizations for email composition. Prerequisites You need Thunderbird with the External Editor extension installed. As of 2026, this extension continues to work with current Thunderbird versions. Install…
Flash Plugin Support in Modern Firefox Adobe discontinued Flash support in 2020, and Firefox removed NPAPI plugin support entirely. This post is maintained for historical reference only. If you need Flash content, consider: Ruffle — An open-source Flash emulator written in Rust that runs in the browser without plugins Standalone Flash player — For archived…
Xen Virtualization: Historical Context and Modern Alternatives This post describes Xen DomU setup procedures from the early 2010s. While Xen remains critical infrastructure for cloud providers like AWS EC2 and Citrix Hypervisor, it’s rarely deployed for new on-premises virtualization projects. For modern Linux virtualization, consider: KVM/QEMU: The default hypervisor in most Linux distributions, better community…
Disabling IPv6 on Linux IPv6 is enabled by default on most Linux distributions. While IPv6adoption has grown, many environments still rely primarily on IPv4, and disabling IPv6 can simplify networking configurations or resolve compatibility issues. Quick Method: Disable via modprobe The most straightforward approach is to prevent the IPv6 kernel module from loading: echo “options…
Taking Screenshots in mpv MPlayer reached end-of-life years ago. Its active fork, mpv, maintains all screenshot functionality with identical or simpler syntax. This guide covers mpv, which handles both single captures and burst sequences. Enable Screenshot Support Screenshot support is built into mpv by default — no filter loading required. However, you can customize behavior…
Installing 32-bit Firefox on 64-bit Linux Running 32-bit Firefox on a 64-bit Linux system is less common than it used to be, but there are still valid reasons: testing web compatibility across architectures, supporting legacy plugins, or working with older systems. This guide covers Fedora and RHEL-based systems, though the core approach applies to other…
Reverting Changes in Git Mistakes happen during development. Git provides several commands to undo changes at different stages—before committing, after committing, or in specific files. Understanding which tool to use depends on where you are in the workflow. Revert the entire working tree before committing If you’ve made changes to multiple files and want to…
Getting System Uptime on Linux The uptime command is the quickest way to check how long your system has been running: $ uptime 22:19:29 up 10 days, 22:26, 5 users, load average: 0.00, 0.00, 0.01 This output shows: Current time: 22:19:29 System running for: 10 days, 22 hours, 26 minutes Active user sessions: 5 Load…
SSH Clients PuTTY remains a solid choice for SSH access from Windows. It’s lightweight, portable (no installation required), and handles key-based authentication well. Download the .exe version for portability. For a more modern terminal experience, Git Bash (included with Git for Windows) gives you native OpenSSH on Windows. If you’re on Windows 10+, the built-in…
Network Connectivity Between Clusters Using iptables and NAT Connecting servers with internal IPs across multiple clusters over the internet is a common infrastructure requirement. While a traditional VPN is the standard approach, you can implement similar functionality using iptables and Network Address Translation (NAT) rules, often with lower overhead than VPN solutions. This method works…
pgrep and pkill: Process Management Commands pgrep and pkill are essential tools for finding and signaling processes by name and attributes. They’re far more precise than grepping ps output and should be your go-to for process management scripts and one-liners. pgrep: Find Process IDs pgrep searches running processes and outputs matching PIDs. All selection criteria…
Understanding paravirt_ops in the Linux Kernel paravirt_ops is an abstraction layer in the Linux kernel that allows the same binary to run efficiently on both bare metal and various hypervisors through runtime patching. Rather than compiling separate kernels for each platform, paravirt_ops lets the kernel detect its environment at boot and optimize itself accordingly. The…
Font Rendering on Fedora with FreeType Bytecode Interpreter Fedora’s default font rendering can look subpar, particularly on laptops with standard LCD screens. TrueType bytecode interpreter (BCI) support significantly improves rendering quality, but licensing restrictions have kept it disabled in Fedora’s default FreeType builds. The TrueType bytecode patents expired years ago, so BCI is now safe…
Creating LVM Volume Groups LVM (Logical Volume Manager) lets you combine multiple physical disks into flexible storage pools. This guide covers creating a volume group from multiple disk partitions—a common setup for servers that need flexible storage allocation across Xen guests, databases, or other demanding workloads. Prerequisites This assumes you have two or more unformatted…
LVM-backed storage for Xen DomU LVM logical volumes are a practical choice for Xen guest storage. They support dynamic resizing, snapshots, and efficient cloning — capabilities that make capacity management and guest provisioning straightforward compared to fixed disk images. This guide covers creating and configuring LVM-backed virtual block devices (VBDs) for Xen DomU instances. Creating…
LVM Snapshots for Fast Virtual Machine Cloning LVM snapshots provide an efficient way to duplicate virtual machines in seconds rather than minutes. Instead of copying an entire filesystem, snapshots leverage copy-on-write semantics—physical blocks are only duplicated when the source or snapshot is modified. This approach works well for any LVM-backed virtualization platform, though Xen is…
Duplicating and Backing Up LVM-Backed VMs from a Remote Server LVM snapshots provide a fast, efficient way to duplicate virtual machines across servers. This technique applies to any LVM-backed hypervisor including Xen, KVM, and Proxmox. The process uses LVM snapshots on the source server, then transfers the snapshot image to the destination using standard Unix…
Checking Firmware Version in Linux The firmware (BIOS/UEFI) on your system contains critical hardware settings and boot information. Knowing your firmware version is essential for updates, compatibility checks, and troubleshooting. Here’s how to find it. Using dmidecode dmidecode is the standard tool for reading the Desktop Management Interface (DMI) table, which stores hardware and firmware…