Most of what goes wrong with Apache 129 goes wrong in a file you did not know it was reading: a rewrite rule that works on your laptop and does nothing on the server, a password prompt that protects one URL but not the same files under another, a 500 error caused by one misspelled word in a hidden file three directories up. Each is a question about which configuration applied to a request, in what order, and who was allowed to write it.
That is why this chapter centers on .htaccess, the per-directory file that made Apache the server of shared hosting and that WordPress 48 and Laravel 2,157 still ship. Apache Essentials to Proxying and Hardening condense the server-wide material; How .htaccess Works to Troubleshooting .htaccess go deep on per-directory configuration and end with complete, tested files you can paste and adapt. Installing packages, systemd 142,543 , firewalls and certificates are in Linux, and PHP-FPM tuning in PHP.
What you will learn
How Ubuntu 225 lays out Apache's configuration, how sections merge, and how a virtual host is chosen
HTTPS with mod_ssl and mod_md, HTTP/2, PHP-FPM, proxying and a hardening checklist
How .htaccess is found, merged and restricted by AllowOverride, and what it costs
mod_rewrite in depth: patterns, conditions, flags, RewriteBase, loops, maps and tracing
Complete .htaccess recipes for security, caching, HTTPS, hotlinking and maintenance mode