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Troubleshooting

Common VPS error messages, diagnosed and fixed.

SSHSecurity

Default SSH Port: What It Is & How to Change It

The default SSH port is 22. Learn why changing it reduces attack surface, how to change it on Ubuntu and Debian, and how to open the new port in UFW and firewall rules.

May 11, 20264 min read
Securityfail2ban

How to Install and Configure fail2ban on Ubuntu & Debian

Install fail2ban to automatically block brute-force attacks on SSH, web servers, and other services. Covers installation, configuration, custom jails, and monitoring.

May 11, 20265 min read
RDPWindows

RDP Port: What It Is, How to Change It & Firewall Rules

Everything about the default RDP port 3389 — how to change it for security, open it in Windows Firewall and UFW, and connect from any device.

May 11, 20264 min read
LinuxUbuntu

add-apt-repository: command not found — Fix for Ubuntu & Debian

Fix 'add-apt-repository: command not found' on Ubuntu, Debian, and WSL in one command. Caused by missing software-properties-common package.

May 9, 20262 min read
LinuxErrors

bash: conda: command not found — Fix for bash & zsh

Fix 'bash: conda: command not found' after installing Miniconda or Anaconda. The shell init block is missing. One-command fix for bash and zsh.

May 9, 20263 min read
LinuxErrors

curl: command not found — Fix for Ubuntu, Alpine & CentOS

Fix 'curl: command not found' on Ubuntu, Debian, Alpine, CentOS, and Docker. curl is missing on minimal Linux images — one-line install per distro.

May 9, 20262 min read
DockerLinux

docker: command not found — Fix for Ubuntu, Debian & CentOS

Fix 'docker: command not found' on Ubuntu, Debian, and CentOS. Docker may not be installed, or your user is not in the docker group. Full install guide included.

May 9, 20263 min read
LinuxErrors

make: command not found — Fix for Ubuntu, Debian & macOS

Fix 'make: command not found' on Ubuntu, Debian, and macOS. Install build-essential (Linux) or Xcode Command Line Tools (macOS) to compile from source.

May 9, 20263 min read
Node.jsErrors

npx: command not found — Fix for Node.js, nvm & Permission Issues

Fix 'npx: command not found' after installing Node.js. npx ships with npm 5.2+. Fix for nvm installs, old Node versions, and broken global PATH.

May 9, 20263 min read
SSHLinux

SSH Connection Refused: How to Fix Port 22 Connection Refused on VPS

Fix 'ssh: connect to host port 22: Connection refused' on a Linux VPS. Covers firewall rules, SSH daemon failures, wrong port, and rescue mode.

May 9, 20263 min read
LinuxDebian

sudo: command not found — Fix for Debian, Docker & VPS

Fix 'sudo: command not found' on minimal Debian installs, Docker containers, and VPS images. Install sudo and add your user to the sudoers group.

May 9, 20263 min read
Node.jsErrors

vite: command not found — Fix for npm, npx & pnpm

Fix 'vite: command not found' after installing Vite locally. Vite is a local dev dependency — run it via npx, pnpm exec, or add it to package.json scripts.

May 9, 20262 min read
LinuxPerformance

VPS High CPU Usage: How to Find and Kill the Offending Process

VPS CPU pegged at 100%? Find and kill the offending process. Covers top, ps, cryptominer detection, and how to resolve high load without losing your server.

May 9, 20263 min read
LinuxErrors

VPS Keeps Rebooting: Fix Unexpected Restart Loop on Linux Server

Why your VPS keeps rebooting itself and how to stop it. Covers kernel panics, OOM killer, hardware watchdog, and reading crash logs after an unexpected restart.

May 9, 20264 min read
LinuxDisk

VPS Out of Disk Space: Fix 'No space left on device' Error

How to fix 'No space left on device' on a Linux VPS. Find what is consuming disk space, clean up safely, and prevent it from happening again.

May 9, 20263 min read
LinuxmacOS

wget: command not found — Fix for macOS, Ubuntu & Minimal Linux

Fix 'wget: command not found' on macOS, Ubuntu, Debian, Alpine, and minimal Linux installs. Includes one-line install commands and a curl fallback.

May 9, 20262 min read
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