  In January 1999, CERN began to develop CASTOR ("CERN Advanced STORage
manager"). This Hierarchical Storage Manager targetted at HEP applications has
been in full production at CERN since May 2001. It now contains more than two
Petabyte of data in roughly 9 million files. In 2002, 350 Terabytes of data
were stored for COMPASS at 45 MB/s and a Data Challenge was run for ALICE in
preparation for the LHC startup in 2007 and sustained a data transfer to tape
of 300 MB/s for one week (180 TB). The major functionality improvements were
the support for files larger than 2 GB (in collaboration with IN2P3) and the
development of Grid interfaces to CASTOR: GridFTP and SRM ("Storage Resource
Manager"). An ongoing effort is taking place to copy the existing data from
obsolete media like 9940 A to better cost effective offerings. CASTOR has also
been deployed at several HEP sites with little effort. In 2003, we plan to
continue working on Grid interfaces and to improve performance not only for
Central Data Recording but also for Data Analysis applications where thousands
of processes possibly access the same hot data. This could imply the selection
of another filesystem or the use of replication (hardware or software).
