LCFG: The Next Generation

1 Abstract This paper describes the most recent version of the LCFG automatic configuration and installation system, originally developed at Edinburgh University around 1993. This version contains a number of significant differences from the original, and has become known as LCFGng (next generation). LCFG provides a configuration language and a central repository of configuration specifications, from which individual Unix machines can be automatically installed and configured. Changes to the central specification automatically trigger corresponding changes in the actual configuration of individual nodes. The system is particularly suitable for sites where the configurations are very diverse (ranging from large servers to laptops), and different aspects of the configurations may be changed frequently, and managed by many different people. LCFG scales to at least medium-size sites (˜1000 nodes). The paper first presents some background and history of the LCFG framework, followed by a general discussion of the large-scale configuration problem. The current implementation of LCFG is then described, noting where, and why, this differs from the original version. Finally, current and future development plans are discussed. 2 Background For many years, the Unix community has recognised the inadequacy of vendor-supplied configuration tools for managing large networks of disparate machines. A wide range of solutions have been proposed and developed by systems administrators, frequently just for their own use. Past proceedings of the Usenix LISA conference 1 give some idea of the scope of these tools, which range from simple cloning mechanisms to more complex database systems.