Computational clusters have become the dominant platform for a wide range of scientific disciplines. Cluster management software is available that allows administrators to specify and install a common software stack on all cluster nodes, and enable centralized control and diagnostics of components with minimal effort. While grid deployments have similar management requirements, they have faced a lack of available tools to address their needs. This paper describes the systems management solutions developed for one such grid deployment, the GEON Grid, a domain-specific grid of clusters for geological research. Machines in GEON grid are geographically dispersed, and must be connected with wide-area networks. GEON provides a standardized software stack across all sites, while allowing controlled local customization. This situation gives rise to a set of requirements that are difficult to satisfy with existing cluster tools. In this paper we describe extensions to the Rocks cluster distribution to satisfy several key goals of the GEON Grid, and show how these wide-area cluster integration extensions satisfy the most important of these goals.