LCSCmd.exe is the main command-line tool in Microsoft Office Communications Server 2007 R2. There are other ways you can work with Office Communications Server 2007 R2 from the command line, namely by running Windows Installer files (which is discussed later in this guide) and scripts, but LCSCmd is the main utility you'll work with from the command line.
Most of what you'll do with LCSCmd has to do with setup and installation. LCSCmd is designed in part to make automated setups possible, and to create scripts that can be run from the command line to check various system states. However, LCSCmd is especially useful for installing Office Communications Server 2007 R2 Enterprise Edition with an Expanded configuration, for the simple reason that it's the only configuration that doesn't have a user interface for the setup. The other two configurations come with setup wizards that walk you through installation of Office Communications Server 2007 R2 and the various server roles, but as of Office Communications Server 2007 R2, there is no user interface option for an Expanded configuration setup. Because of that, this guide includes a topic on Command-Line Deployment of Office Communications Server 2007 R2 Expanded Configuration.
This guide discusses LCSCmd, shows you the numerous parameters, and takes you through the many tasks you can perform with LCSCmd. It also covers running Windows Installer packages (.msi files) from the command line, something you'll need to know about in order to install the various server components. Finally, it lists the steps required to perform a command-line installation.