Migrating Open Science Grid to RPMs*

We recently completed a significant transition in the Open Science Grid (OSG) in which we moved our software distribution mechanism from the useful but niche system called Pacman to a community-standard native package system, RPM. In this paper we explore some of the lessons learned during this transition as well as our earlier work, lessons that we believe are valuable not only for software distribution and packaging, but also for software engineering in a distributed computing environment where reliability is critical. We discuss the benefits found in moving to a community standard, including the abilities to reuse existing packaging, to donate existing packaging back to the community, and to leverage existing skills in the community. We describe our approach to testing in which we test our software against multiple versions of the OS, including pre-releases of the OS, in order to find surprises before our users do. Finally, we discuss our large-scale evaluation testing and community testing, which are essential for both quality and community acceptance.