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Hi Patrick, You are quite right that the design of the cache does impose limits on file names. The oss was designed almost 10 years ago when there were no integrated LVM's and few that worked really well and users kept path names to less that 200 characters. Over the years, as LVM's became common, the oss turned into the "poor man's LVM". In general, we don't recommend using it if you have ready access to a suitable LVM. While, yes, you do give up some features (like fine-grained recoverability and application-directed partition selection) the other limitations may be even more annoying. We'll make sure that this restriction is prominently mentioned in the manual. The path you've chosen is about the only one that will work (i.e., copying off the data and creating a single filesystem using an LVM). Now, we do have some ideas on how to remove the pathname length restriction but wonder if it's really worth the trouble of doing it, given that LVM's provide practically the same basic features. Any thoughts? Andy P.S. What's the driving force for very long path names at your site? On Sat, 1 Mar 2008, Patrick McGuigan wrote: > Hi, > > Some of our data servers have two disks and I am using the oss.cache > directive to use both disks to support a single namespace. However, it looks > like the users of our applications have already run into a problem. All of > the files are stored in one directory (for a single cache) and the filename > is the full namespace path with "/" substituted with "%". Our problem arises > from the fact that full namespace path is now limited to the leafname length > of the filesystem (255 characters) when writing to the cache directory. > > I see a couple of ways to mediate the problem; removing one disk or using and > LVM to create one drive in the OS. I am curious if there are other > alternatives? > > If I have to move to one disk, I would like to migrate the data in the > existing caches to other data servers while I rework the existing system. > What is the best way to migrate this data? I am planning on taking the > "problem" data server off-line and use xrdcp to move the data to the other > servers. > > Regards, > > Patrick >