linux

Resolve SSH 'Permissions 0777 for id_rsa are too open' error. Set correct permissions: chmod 600 ~/.ssh/id_rsa, 700 ~/.ssh on Linux/macOS. Windows icacls fix included. Secure private keys properly.

Efficiently find files containing specific text on Linux with grep, find, and xargs. Tips for system-wide searches, handling binaries and filenames with spaces.

Step-by-step guide to install and configure Gosplugin on Debian 12 with Yandex Browser for Gosuslugi access using electronic signatures. Fix infinite download loops, native messaging, and CryptoPro integration.

Learn mkdir -p equivalents to create a directory and missing parent directories in Linux/macOS, Python (os.makedirs), PowerShell (New-Item), Node.js, Java. Avoid race conditions with exist_ok=True.

Learn why iptables -C command fails to recognize NAT rules and how to properly verify iptables NAT rules using the correct syntax with -t nat option.

Discover the best open-source speech-to-text tools for Linux. Compare accuracy for Russian and English. Find privacy-focused solutions that protect your data.

Discover what the ^M character means in Vim—it's a carriage return from Windows CRLF line endings. Learn to remove ^M from .vimrc files using :%s/\r//g, :set ff=unix, or dos2unix to fix configuration issues and ensure Unix compatibility.

Ensure cron jobs run if PC sleeps using systemd timers with Persistent=true or anacron. Set up Time Machine-style versioned backups on Linux with Timeshift, rsync snapshots for incremental file versioning after wake-up.

Resolve Alt Linux Server 11 GNOME WiFi adapter not found issue. Change NM_CONTROLLED=yes in /etc/net/ifaces, diagnose with lspci, dmesg, nmcli. Safe fix for NetworkManager unmanaged interfaces.

How the Linux kernel build system uses built-in.a and KBUILD_VMLINUX_LIBS to link object files into vmlinux, and how built-in drivers differ from modules.

Master iptables rules for WireGuard wg0: drop all incoming packets except UDP port 51821. Why ACCEPT+DROP beats single negated rule. Avoid pitfalls like negation logic, rule ordering, connection tracking, INPUT vs FORWARD chains.

Learn to detect system clock tampering and time jumps in C++20 for cross-platform security agents. Use std::chrono::system_clock vs steady_clock polling, Windows Event ID 4616, Linux timerfd for reliable protection against clock manipulation.

Learn why sudo chroot /mnt /bin/bash fails on Ubuntu with 'no files below /bin/bash' error. Fix by bind mounting /dev, /proc, /sys, /run, checking libraries with ldd, and copying resolv.conf. Step-by-step guide for chroot Ubuntu setups.

Why JxBrowser's Chromium subprocesses show massive VIRT (32GB-1TB+) on Linux in top, VIRT vs RSS explained, and fixes: Chromium flags via EngineOptions, ulimit, cgroups, /dev/shm for Docker to prevent JavaFX JVM crashes.

Fix slow Ollama embeddings in ChromaDB on Linux VM without CUDA: batch requests, disable Posthog telemetry, ignore benign warnings. Run fully local for privacy and speed up email embedding performance.

Step-by-step guide to reformat HGST HUS723020ALS640 SAS drive from 520-byte to 512-byte sector size. Use IT-mode HBA, sg_format from sg3_utils, vendor tools. Hardware needs, RAID vs HBA, firmware risks explained.