Networking

The error message "Error 521: Web server is down" indicates an issue with the server. This guide explains common causes and provides methods to troubleshoot and resolve error 521.

Reducing DNS lookup time improves the performance of your website in a number of important ways, including Faster website and individual component loading, reduced network latency, and better server utilization. This article explains the importance of reducing DNS lookups and provides ten tips to optimize DNS lookups on your website.

SSH (Secure Shell) and SSL (Secure Sockets Layer) protocols are cryptographic technologies that ensure secure communication over the internet. This guide explains how they work, what makes them different, and which one to use.

Setting up a static local network IP address on a device ensures that its location on the network persists across reboots. Static IPs are especially useful when accessing devices remotely (e.g., over SSH). This tutorial shows you how to configure a static IP address on Raspberry Pi.

This tutorial shows the steps required for changing the default SSH port into a different one. A different port adds an extra layer of protection to the connection.

This guide explains what error 520 means, what causes it, and how to fix it.

Postfix is a free mail transfer agent that uses SMTP to route and deliver emails. This tutorial shows how to configure Postfix to use an external SMTP server.

The telnet command allows users to establish an unsecure connection to remote servers or machines. This tutorial shows how to use telnet and showcases its useful features.

Do you use the SSH config file? Learn how to utilize the SSH config file to automate and streamline SSH connections.

Docker containers are particularly handy when an application such as a web server needs to preserve its configuration across different environments. This article demonstrates two methods to deploy Apache web server using Docker.