Cacti is an open-source, web-based network monitoring, performance, fault and configuration management framework designed as a front-end application for the open-source, industry-standard data logging tool RRDtool.

Nagios is an event monitoring system. Nagios offers monitoring and alerting services for servers, switches, applications and services. It alerts users when things go wrong and alerts them a second time when the problem has been resolved.

Active Directory (AD) is a directory service developed by Microsoft for Windows domain networks. It provides a centralized system for managing and organizing network resources, including users, computers, groups, printers, and other network-related objects. Active Directory plays a crucial role in authentication, authorization, and directory services within a Windows-based environment.

Virtualization is a process that allows for more efficient use of physical computer hardware and is the foundation of cloud computing.

Zimbra is an email and collaboration platform developed by Zimbra, Inc. It provides a suite of communication and collaboration tools, including email, calendaring, contacts, document sharing, and task management. Zimbra can be deployed as an on-premises solution or in the cloud.

Borg Backup is a deduplicating backup program that offers efficient storage and backup capabilities. It provides encryption, compression, and support for incremental backups, making it suitable for both local and remote backups.

The Domain Name System (DNS) is a hierarchical and distributed naming system for computers, services, and other resources in the Internet or other Internet Protocol (IP) networks. It associates various information with domain names (identification strings) assigned to each of the associated entities.

A web server is software and hardware that uses HTTP (Hypertext Transfer Protocol) and other protocols to respond to client requests made over the World Wide Web. The main job of a web server is to display website content through storing, processing and delivering webpages to users.

Nmap (Network Mapper) is a powerful open-source network scanning tool used for discovering hosts and services on a computer network, thus creating a "map" of the network. It's widely used by network administrators, security professionals, and ethical hackers for network inventory, security auditing, and vulnerability assessment.