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Hi Brian, Adding to what Fabrizio said... If for some reason you still think that a plug-in is more appropriate for HDFS then you should really consider writing an OSS plug-in as opposed to an OFS plug-in. If you write a plug-in at the OFS layer then you are responsible for implementing all of the logical functions performed by that layer. These include, among others, authorization, cluster management, extended name space functions, safe persistence, and MSS co-ordination. The OSS layer is merely responsible for conveying data to/from the underlying storage system as well as basic name space operations to support itself. To me it sounds like HDFS integration is better suited at the OSS layer. Plus there's much less to do at that layer. Andy On Fri, 5 Jun 2009, Fabrizio Furano wrote: > Hi Brian, > > if I understood correctly it does not seem difficult. Just mount your fs > partitions into a server, install xrootd there and make it export those > partitions by hiding their prefix through the localroot setting. > > Imo the easiest way is to use the setup used by alice, pretty generic and > bundled. A pointer to the instructions is this one: > > http://savannah.cern.ch/project/xrootd > or > http://alien.cern.ch/twiki/bin/view/AliEn/HowToInstallXrootdNew > > Of course the option to start it manually and accessing the full > configuration is always ok. The docs are here: > > http://xrootd.slac.stanford.edu > > Fabrizio > > Brian Bockelman wrote: >> Hey all, >> >> I've been asked by a few folks about adding an Xrootd interface to the file >> system we use locally, HDFS. HDFS's security mechanism make it so the only >> true way to be secure is to only allow access from within the local >> cluster; I'd like to be able to securely export the file system to >> ROOT-based applications running on the local campus (but not transfer it >> across the world). HDFS has a FUSE interface which implements most of the >> POSIX API, but apparently not enough to have xrootd work directly on top of >> it :) >> >> However, HDFS has a pleasant, simple C interface: >> >> http://svn.apache.org/repos/asf/hadoop/core/trunk/src/c++/libhdfs/hdfs.h >> >> I'm trying to provide feedback to those who want it about how hard this >> project would be. Could someone help me determine: >> >> 1) What exactly would need to be implemented? (I'm a bit new to xrootd; I >> believe I'm looking at implementing a new subclass of OFS?) >> 2) What would be needed to do a minimal working prototype that I could show >> to someone. >> 3) Is there a sample "simplest implementation" that I could base a >> prototype off of? >> 4) What documentation exists to help me along the way? >> >> Thanks! >> >> Brian >