Lana Abadie (CERN)
The DPM (Disk Pool Manager) provides a lightweight and scalable managed disk storage system. In this paper, we describe the new features of the DPM. It is integrated in the grid middleware and is compatible with both VOMS and grid proxies. Besides the primary/secondary groups (or roles), the DPM supports ACLs adding more flexibility in setting file permissions. Tools to interact with the DPM at different levels have been extended so that site managers can more dynamically configure and manage their DPM in a consistent way. In addition to rfio and gsiftp, users can now use the xrootd and https protocols to access the DPM. A new version of Storage Resource Manager (SRM) interface, v2.2 has been implemented. One of the novelties is the reserve space concept, useful to guarantee space for a specific user or a group during a given period of time. DPM has been deployed in roughly 80 Tier-2 sites and in several medical institutes. Unlike physics data, medical data is very sensitive. The DPM will offer the possibility to encrypt data throughout the process in a very secure way by implementing a key-distributed system. Performance has been improved by the use of bulk queries. Stressing tests have shown a good robustness of the DPM against concurrent accesses.