VNC (Virtual Network Computing) provides a graphical remote desktop connection to Linux servers. It’s straightforward to set up and useful when you need GUI access to a headless or distant system. Installation On the server side, install a VNC server package. TigerVNC is the most reliable choice across distributions: Debian/Ubuntu: sudo apt install tigervnc-server tigervnc-common…
SSHFS (SSH Filesystem) mounts a remote filesystem over SSH, letting you interact with remote files as if they were local. It uses SFTP under the hood, so no additional server configuration is needed beyond SSH access. Install SSHFS on CentOS 7 # Enable EPEL repository sudo yum install epel-release # Install sshfs sudo yum install…
CONFIG_HZ sets the kernel’s internal timer interrupt frequency (measured in Hz). This determines how often the kernel’s scheduler runs and how fine-grained process preemption can be. The default value is typically 250 Hz on most distributions, though some set it to 1000 Hz for lower latency workloads. Higher CONFIG_HZ values (like 1000 Hz) reduce scheduling…
Ubuntu boots to the graphical desktop by default, but you can change it to boot directly to a text-mode login prompt. This is useful for headless servers, troubleshooting, or resource-constrained systems. The method depends on your init system. Modern Ubuntu uses systemd, but the GRUB approach still works if you need it. Using systemd (recommended)…
Adobe Flash Player reached End of Life on December 31, 2020, and Adobe blocked all Flash content from executing in 2021. Installing Flash Player on CentOS 7 in 2026 is neither practical nor recommended—the plugin won’t execute Flash content anyway, and doing so introduces security vulnerabilities to your system. If you’re still running CentOS 7,…
[md] The RTL8192cu is a legacy USB WiFi adapter that’s still in use, but it has known stability issues on modern kernels. If your adapter keeps dropping connections or fails to resume after sleep, you’re likely hitting the same power management bug that affects many devices. ## Disable Power Management The most reliable workaround is…
aclocal is part of GNU Autotools and generates aclocal.m4 files needed by the autoconf build system. It’s typically required when working with projects that use traditional Autotools-based builds. Quick Install sudo dnf install automake The automake package provides aclocal, automake, and related utilities. Verify the Installation After installation, confirm aclocal is available: aclocal –version You…
Configuring multiple static IP addresses on a Xen VM is useful for hosting multiple services, SSL certificates, or failover scenarios. The approach depends on your underlying Linux distribution and whether you’re using traditional network configuration or modern network managers. Using ip Command for Immediate Changes The quickest way to add a secondary IP is with…
NFS squashes root access to an anonymous user (typically nobody) by default as a security measure. When a client connects as root, the server remaps that user to an unprivileged account, preventing root from having unrestricted access to exported shares. This can cause permission issues if your application genuinely requires root-level file operations. Using no_root_squash…
PARSEC is a widely-used CPU-bound benchmark suite containing real applications and complex third-party library dependencies. The installation can be challenging due to these external requirements, but following this guide will get you up and running. Prerequisites Before starting, install the required build tools and libraries: sudo apt-get update sudo apt-get install build-essential pkg-config gettext autoconf…
The NAS Parallel Benchmarks (NPB) remain a standard tool for evaluating HPC system performance, though landscape has shifted toward additional metrics like HPCG and memory bandwidth tests. This guide covers installation and basic usage. Prerequisites Before installing NPB, you’ll need: Fortran compiler — gfortran is the standard choice on most systems MPI implementation — OpenMPI…
If you already have PHP and nginx running on Rocky Linux 9 and need to add or update glibc, glibc-common, and GD libraries independently, you can do so safely without disrupting your existing installation. Understanding the dependencies glibc: The GNU C Library — the core runtime library for nearly all C programs on Linux glibc-common:…
In Go, a string is a read-only slice of bytes, while a rune is an alias for int32 representing a Unicode code point. Understanding this distinction is essential when you need to work with individual characters, especially in multilingual text. Basic Conversion The simplest approach is direct type conversion: s := “Hello, 世界” runes :=…
Sending output to stderr keeps error messages separate from normal program output, making it easier to redirect and filter logs in shell scripts and pipelines. Basic Approach with fmt The simplest method uses fmt.Fprintln() with os.Stderr: package main import ( “fmt” “os” ) func main() { fmt.Fprintln(os.Stderr, “This is an error message”) } This writes…
Error handling is fundamental to Go development. Often you’ll need to convert an error to a string for logging, displaying to users, or including in API responses. Go provides several straightforward approaches. Using the Error() Method Every error in Go implements the error interface, which has a single method: Error() string. The simplest conversion is…
The kernel log buffer (dmesg) outputs timestamps in seconds since boot by default, making it difficult to correlate events with wall-clock time or other system logs. Here’s how to convert them to human-readable format. Using journalctl Instead of dmesg The modern approach is to use journalctl, which handles timestamp formatting automatically: journalctl -b This shows…
The traditional Node.js approach uses require(). Create a module that exports functions, then import them where needed. exporting functions (math.js): function add(a, b) { return a + b; } function subtract(a, b) { return a – b; } module.exports = { add, subtract }; importing in another file (app.js): const { add, subtract } =…
Processing files line by line is a common task in Go. Here are the practical approaches, from simplest to most flexible. Using bufio.Scanner The most straightforward method uses bufio.Scanner, which handles line splitting automatically: package main import ( “bufio” “fmt” “log” “os” ) func main() { file, err := os.Open(“input.txt”) if err != nil {…
Many Go functions accept an io.Reader interface. To pass a string to these functions, use strings.NewReader, which wraps the string without copying it—the data is read directly from the original string. Basic Usage import “strings” reader := strings.NewReader(“Hello, World!”) This creates an io.Reader that can be passed to any function expecting that interface. The reader…
Grep handles tab characters in a few different ways depending on your needs. Here’s what actually works. Using \t with extended regex The most straightforward approach uses grep’s extended regular expressions (-E flag): grep -E ‘\t’ filename.txt This matches any line containing a literal tab character. The \t escape sequence is interpreted as a tab…