howto

Fixing Dovecot Diffie-Hellman Parameter Error

Learn how to fix Dovecot's Diffie-Hellman key exchange requested SSL error by generating DH parameters with OpenSSL and configuring ssl_dh properly.

Checking DNS Zone Files

Learn why validating DNS zone files is critical for website reliability and email delivery. Discover practical tools and best practices to prevent costly DNS configuration errors.

Synchronize Files Preserving Remote Ownership and Permissions with rsync

Learn how to use rsync to synchronize local and remote files without altering ownership and permissions on the remote server, ensuring consistent file management across systems.

Find Lines in One File Not Present in Another Using `grep`

Learn how to use the powerful `grep` command in Unix/Linux to compare text files and identify lines unique to one file. Simplify file comparison with this quick and flexible technique.

How to Prevent SSH Timeout on Linux Systems

Prevent SSH timeouts on your Linux machine with a simple configuration change. Follow our quick guide to keep your SSH connection active during periods of inactivity.

How to Escape Colons in CSS Classes in JavaScript

Learn how to select HTML elements with special CSS classes like 'empty:hidden' using JavaScript's document.querySelectorAll method.