dCache things Paul Millar … on behalf of the dCache team

Agility in a Changing World Adapt to changing environment Adapt to changing access methods Adapt to different users

Flexibility through plugins dCache has always been flexible Very flexible configuration Little known secret, dCache has always been extensible (adding new functionality). Added support for loading plugins when starting If there's something you can't configure, write a plugin!

gPlazma: flexible identity management Old gPlazma wasn't flexible Monolithic operations: either succeed or fail Rewrote to use a plugin approach based on PAM Plugins can cooperate to complete a login step Plan to add support for Federated Identity Part of the LSDMA project Good test of gPlazma flexibility In good shape if WLCG moves away from X.509

gPlazma: flexible identity management LSDMA Non-HEP users: no grid certificate /X.509 Web-based solutions are preferred (portals for metadata-based work), LSDMA WP1 is Federated AAI, dCache has flexible identity management system Plugins allow adding new functionality to work with existing Useful if WLCG moves away from pure X.509.

Federated storage: the idea Client-driven Find all replicas Choose “best” one Open data to best replica Federated storage Open data Make request to central end-point Find all replicas Chooses “best” one Reply with redirect Follow redirect The idea: Access the data from wherever is “closest” Don't be explicit: always use a “central” endpoint, which redirects client to (hopefully) the best choice Currently for read-only (e.g., recovery) Benefits: Move logic to central components Easier to keep up-to-date Allows stateful decision Needs a protocol with redirection support: xrootd and HTTP NB. needs a network protocol that supports redirection: xrootd or HTTP NB. file may have different paths in different storage systems

Federated storage: the implementation xrootd-based Experiment-driven CMS pushing, ATLAS are investigating xrootd door has plugins: Allows global-to- local path mapping Plugin for CMS and ATLAS developed Experiments are involved in plugins HTTP-based Collaboration between DESY and CERN IT- GT/DMS Allows use of industry standard software Can browse files Currently in the early stages Prototype software written Initial performance tests are encouraging

dCache scientific cloud Easy way to store, use and share data Form new collaborations Currently: Users get their own area HTTP/WebDAV for direct access to files, Use web-browser for managing stored files, drag-and-drop support Data is available on compute resources (via NFS) Files are available for copying (via GridFTP) Active collaboration with Globus Online Longer-term: Provide DropBox-like storage that allows scientific analysis User sees only their own data (and what's shared)

Conclusion dCache is agile software flexibility achieved through plugins more than SRM, more than grid storage dCache is back-bone of HEP analysis ~50% of data stored in dCache Get involved! If you don't have dCache, install it If you have dCache, what else can you get it to do?

Image credits Skateboard: Tim Drivas (from flickr) Horses: Verity Borthwick (from flickr) Keyboard: Who Are You? psd (from flickr)