When adding new modules, you have to keep two things in mind: The modules you need (Left side) and the server(s) you want them on (Right side).
ClusterCS currently offers installation and management for 17 modules:
1. apache - the world's most used web server. Highly recommended in most environments set on serving web content and a core component of the LAMP stack
2. lighttpd - lighttpd is a secure, fast, compliant, and very flexible web-server that has been optimized for high-performance environments. It has a very low memory footprint compared to other webservers and takes care of cpu-load. Its advanced feature-set (FastCGI, CGI, Auth, Output-Compression, URL-Rewriting and many more) make lighttpd the perfect webserver-software for every server that suffers load problems
3. haproxy - very fast and reliable solution offering high availability, load balancing, and proxying. It is particularly suited for very high traffic web sites and powers quite a number of the world's most visited ones. Recommended by the ClusterCS team!
4. php - The core module needed to compile, run and serve PHP scripts and web pages
5. iptables - an application that allows configuration of the Linux firewall, for IPv4 protocol. Highly recommended by the ClusterCS team!
6. proftpd - A high performance, very secure FTP server
7. nginx - high-performance HTTP server and reverse proxy, as well as an IMAP/POP3 proxy server. NGINX is known for its high performance, stability, rich feature set, simple configuration, and low resource consumption
8. mysql - is an open-source relational database management system. A core component of the LAMP stack.
9. mysql-cluster - is a technology providing shared-nothing clustering and auto-sharding for the MySQL database management system. It is designed to provide high availability and high throughput with low latency, while allowing for near linear scalability
10. mariadb galera cluster - is a synchronous multi-master cluster and database replication for MariaDB
11. postfix - A fast, easy to administrate and secure mail server
12. storage_location - a mandatory module designed by ClusterCS team which manages the server storage for both single-server setups, as well as clusters
13. roundcube - A browser-based IMAP client, providing the full functionality of an e-mail client
14. fail2ban - a service that scans log files to detect possible intrusion/malicious attempts, and temporarily blacklists the IPs. Useful against brute-force attacks
15. memcached - a distributed memory object caching system intended for use in speeding up dynamic web applications by alleviating database load
16. stunnel - an application used to provide SSL/TLS tunneling service, enabling secured TLS/SSL connections. Used for communicating over HTTPS.
17. phpmyadmin - a tool written in PHP, used to manage and administrate mySQL databases over the web
18. spamassassin - an anti-spam platform used to filter spam e-mails
19. clamav - an open source antivirus engine for detecting trojans, viruses, malware & other malicious threats
20. varnish - is a web application accelerator also known as a caching HTTP reverse proxy.
21. redis - is an open source in-memory data structure store, used as a database, cache and message broker. It supports data structures such as strings, hashes, lists, sets, sorted sets with range queries, bitmaps, hyperloglogs and geospatial indexes with radius queries
22. pacemaker - is a high-availability cluster resource manager, it achieves maximum availability for your cluster services (a.k.a. resources) by detecting and recovering from node- and resource-level failures