Networking
ProFTPd Server with virtual users and in SFTP mode
Working with Vsftpd as FTPS server with virtual users and SSL certificates in Debian or Ubuntu
Understanding Key Differences Between FTP, FTPS and SFTP
Active and Passive FTP Simplified - Understanding FTP Ports
How to test SMTP and IMAP servers using the telnet command-line - part I - SMTP
Most secure SSL/TLS configuration for Apache, Nginx, Postfix, Dovecot, HAProxy and other
Rewrite uri to lowercase in nginx and apache webserver
Nginx Location manual
How list all available Apache webserver variables
apache mod_rewrite module guide - part 2