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SSH connections dropping during idle periods is a persistent issue in production environments. Both client and server configurations provide built-in keep-alive mechanisms designed specifically for this problem. Stop running while true; do uptime; sleep 30; done — there are proper solutions. Client-side configuration Per-user SSH config Add to ~/.ssh/config: Host * ServerAliveInterval 60 ServerAliveCountMax 3…
When verifying file integrity on Linux, you’ll typically reach for one of several checksum utilities. A natural question: which one is fastest? The answer depends heavily on whether I/O or CPU is your bottleneck. Disk I/O Dominates on Most Systems In realistic scenarios with typical storage, disk I/O is almost always the limiting factor. Test…
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…
MKV files encoded with AC3 or DTS audio won’t play sound on most iOS and Android devices. These are proprietary formats with licensing restrictions—mobile players either don’t support them or refuse to decode them by default. The video plays fine, but you get silence. The solution is straightforward: re-encode the audio track to AAC or…
When writing to disk, you need to know if space is available — especially in systems software, daemons, and critical applications. The POSIX statvfs() call provides filesystem statistics across all POSIX systems, making it more reliable than Linux-specific alternatives like statfs(). The statvfs() API Include the required header: #include <sys/statvfs.h> Function signature: int statvfs(const char…
Vim is generally fast, but dozens of plugins can create noticeable slowdowns. Since Vim’s core remains single-threaded, any blocking operation in a loaded plugin will freeze your editor until it completes. Rather than disable plugins randomly, use Vim’s built-in profiling tools to identify the actual culprit. Profile Vim Startup Time The fastest way to find…
The /etc/fstab file defines how Linux mounts filesystems at boot and controls mounting behavior for both the system and individual users. Understanding its format and options is essential for reliable storage management. File Format and Fields Each line in /etc/fstab represents one filesystem. Fields are separated by whitespace (tabs or spaces), and lines beginning with…
If you’re using an iPhone set to English but living outside the US, you’ve probably noticed US holidays cluttering your Calendar app. This happens because iOS ties holiday calendars directly to your region setting — not your language preference. Why US Holidays Appear by Default The Calendar app automatically subscribes to holidays based on your…
Playing YouTube audio in the background on iPhone is restricted by design—the official YouTube app only supports it with a Premium subscription. Here are the legitimate approaches and their tradeoffs. Browser Method (Safari/Firefox) The most common workaround uses Safari or Firefox to trigger iOS media controls: Open Safari and navigate to youtube.com (or youtube-nocookie.com) Play…
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…
SSD storage is standard across modern hosting providers. DreamHost and competitors have shifted entirely to SSD-backed shared hosting. The marketing claim of “200% faster page loads” deserves skepticism, but SSD-backed hosting does deliver measurable I/O improvements for realistic workloads. This post covers practical performance measurement techniques on a shared hosting account where you lack root…
Free VPNs on iOS have legitimate uses—testing geolocation-dependent content, accessing region-locked resources, or bypassing network restrictions. But understand the tradeoffs: free providers often log traffic, inject ads, sell bandwidth, or disappear without notice. Use free VPNs only for non-sensitive browsing. For actual security work or traveling to high-risk regions, a paid provider with a documented…
Sharing internet from a Windows PC to an iPhone via USB is possible but requires careful network configuration. This is less common than tethering the other direction, but useful when you need a stable wired connection without draining your phone’s battery. Prerequisites Windows 10 or Windows 11 iPhone with iOS 12 or later USB-A to…
When SSH fails but the daemon still runs, or when kernel panics strike, you need automated recovery without physical access. This guide covers three essential techniques: forcing reboots when the system is unresponsive, auto-recovery from kernel panics, and alerting you when it happens. Force a reboot when SSH is unresponsive If a server stops responding…
Shrinking an ext4 filesystem on LVM is riskier than expanding—it requires the filesystem offline and careful size planning. The operation can take hours on large volumes, and mistakes can destroy data. This guide walks through the safe path with verification at each step. Prerequisites Before starting: Backup everything. A full backup of the data being…
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…
WhatsApp doesn’t have a native iPad or iPod Touch app, but you can access your messages through WhatsApp Web, which works reliably on any tablet with a browser. Here’s how to set it up and what to know about using it. Setting Up WhatsApp Web on iPad WhatsApp Web requires an active WhatsApp account on…