What is required on a managed node for Ansible to connect and manage it?

Ansible is an agentless automation tool, meaning it doesn't require special software installed on the managed nodes. Instead, it relies on standard, widely available protocols. For Linux and Unix-like systems, and many network devices, Ansible uses SSH (Secure Shell) for communication, command execution, and file transfers. Therefore, an SSH server must be running on the managed node to allow Ansible to connect and manage it. While Ansible is commonly used with Linux servers and Cisco devices, it can manage various operating systems and platforms as long as a suitable connection plugin (like WinRM for Windows) is available. Ad hoc commands are a feature of Ansible, not a requirement for the managed node. Ansible Tower (now Red Hat Ansible Automation Platform) is a web-based UI for managing Ansible projects, not a component required on the managed nodes themselves.