Distributing CMS Data between the Florida T2 and T3 Centers using Lustre and Xrootd-fs

We have developed remote data access for large volumes of data over the Wide Area Network based on the Lustre filesystem and Kerberos authentication for security. In this paper we explore a prototype for two-step data access from worker nodes at Florida Tier3 centers, located behind a firewall and using a private network, to data hosted on the Lustre filesystem at the University of Florida CMS Tier2 center. The Tier2-Tier3 links are 10 Gigabit per second, and the typical round trip times are 10-15 msec. For each Tier3 center we use a client which mounts securely the Lustre filesystem and hosts an XrootD server. The worker nodes access the data from the Tier3 client using POSIX compliant tools via the XrootD-fs filesystem. We perform scalability tests with up to 200 jobs running in parallel on the Tier3 worker nodes.