Network speed varies dramatically across connection types. Here’s a practical breakdown of real-world performance across different technologies, using actual test data and modern measurement approaches. Historical Context and Modern Relevance While 2G and 3G networks are largely deprecated in most developed regions by 2026, understanding their performance characteristics remains relevant for: Legacy system maintenance in…
ns (Network Simulator) is a discrete-event simulator used primarily for research and educational purposes in networking. The two major versions—ns-2 and ns-3—are substantially different in architecture and usage patterns. This guide covers installation on current Fedora systems. Installing ns-2 on Fedora Note: ns-2 is legacy software and requires significant compatibility workarounds on modern systems. Consider…
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 can mount and with what…
ns-2 reached end-of-life in 2011 and is no longer maintained. If you’re looking to simulate network behavior, you should use ns-3 instead, which is actively developed and provides significantly better accuracy and modern tooling. Why ns-3 Over ns-2 ns-2 was influential in academic networking research, but its architecture has fundamental limitations that became apparent over…
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 server administrator to…
Flash Player reached end-of-life on December 31, 2020, and modern browsers no longer support it. However, if you’re working with legacy systems, archived content, or old web applications that still require Flash, here’s what you need to know about the historical setup and modern alternatives. The Original Setup (Historical Reference) On 64-bit Linux with Firefox,…
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 support, and tighter kernel integration Proxmox VE…
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 must match unless you use alternatives…
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 Core Problem paravirt_ops Solves Traditional virtualization…
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 to enable. While FreeType 2.13+ ships with BCI…
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 used here as an example. Note: Xen…
Xen remains a production hypervisor used by AWS EC2, Citrix Hypervisor, and other cloud providers, though most general-purpose Linux distributions have shifted toward KVM as their default. If you’re working with Xen in production or developing drivers, understanding its source code layout is essential. Top-Level Directory Structure The Xen source repository (hosted on xenbits.xen.org) is…
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 tools. Scenario Source server: 10.0.0.10 with VM stored in /dev/vg_xen/vm-10.0.0.123…
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 the logical volume Start with…
Xen remains a production-grade hypervisor used in enterprise environments (AWS EC2, Citrix Hypervisor), though KVM has become the default for most Linux distributions. This guide covers building a stable Xen Dom0 on current Fedora releases using modern kernel sources. Hardware Considerations This guide assumes server-class hardware with: Intel or AMD processor with virtualization extensions (VT-x…
A Fedora Live USB lets you boot directly into a Fedora environment without modifying your hard drive. You can use it to test Fedora, troubleshoot your system, or perform a fresh installation. This guide covers modern tools and workflows for creating bootable USB media. Back up any data on your USB stick first — the…
Xen remains production-grade virtualization for specific use cases (AWS EC2, Citrix Hypervisor), but most Linux distributions default to KVM. This guide covers Xen DomU setup using modern tools and practices. For new deployments, evaluate KVM/libvirt or container solutions like Podman/Kubernetes first. Storage Setup Create a file-backed virtual block device (VBD) for your DomU. File-backed storage…
MPlayer and mencoder are obsolete. FFmpeg and mpv (the actively maintained fork of MPlayer) are the standard tools for video manipulation on Linux systems today. While some MPlayer syntax still works in mpv, FFmpeg is more performant, better documented, and handles modern codecs reliably. This guide covers practical tasks using FFmpeg and mpv, with mpv…
Xen remains a production hypervisor for enterprise deployments (AWS EC2, Citrix Hypervisor), though KVM has become the default for most Linux distributions. If you’re deploying Xen in 2026, you’ll likely be working with recent stable releases rather than the legacy versions covered in older guides. This guide covers building a modern Xen Dom0 environment on…
MPlayer and MEncoder are no longer actively maintained, but they’re still available through RPM Fusion if you need them for legacy content or specific workflows. Most users should consider modern alternatives like mpv (MPlayer’s successor) or ffmpeg for transcoding, but this guide covers the traditional setup. Enable RPM Fusion Repository RPM Fusion hosts packages Fedora…