ClusterSSH is a Perl-based cluster administration tool that provides a graphical console (using Tk) to manage multiple SSH (or other protocol) sessions simultaneously. It allows users to define clusters via configuration files, expand hostnames using shell-style ranges, and replicate keystrokes from a master console to all connected terminal windows. The architecture is monolithic, centered around the App::ClusterSSH module, with distinct sub-modules handling configuration, cluster resolution, host parsing, and window management via X11::Protocol. It relies heavily on the X11 protocol for event injection into child xterm processes, making it tightly coupled to X11 environments but highly effective for its specific use case of synchronized cluster management.