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Hi Fabrizio, On Mon, 17 Jul 2006, Fabrizio Furano wrote: > Issue 1: > suppose that you have a cache file system with 2 dirs, where you want to > write: > > oss.cache public /kanga/prd1 > oss.cache public /kanga/prd2 > > it seems that if one directory of the cache file system is not writable > (e.g. prd1 by mistake) the data server can choose to use it anyway, > causing problems. It should detect this and choose the other one. Yes, specifying a r/o cache makes little sense. I will have to look to see if I can actually determine this is r/o and issue a warning and remove that cache specification from the config. > Issue 2: > let's suppose that we want 2 cache file systems in a data server, to > avoid the "flat" allocation made by the server. Here is an example: > > oss.cache skm /kanga/skm1 > oss.cache skm /kanga/skm2 > oss.cache prd /kanga/prd1 > oss.cache prd /kanga/prd2 > xrootd.export /prod > xrootd.export /skim > > The config documentation says (or, at least I understand from it) that > you can pass (through the open request) the oss.cgroup directive via > opaque information specifying the cache group you want to write to. > Well, we were unable to make it write /prod to the cache group "prd". It > seems that the server always arbitrarily chooses the cache directory it > wants between all the entries. That can be a bug as you are the first one to try this. I will have to look at this. Does debug output show anything? > Anyway, even if we make it work, or even if we understand why we were > not able to, the best solution possible imho would be to associate a > cache group to an exported directory, maybe in the xrootd.export directive. That would be another way of doing this. > e.g. with directoves like: > > xrootd.export /prod prd > xrootd.export /skim skm Actually, I am in the process of merging the oss.path directive with the export directive so that all paths need to be specified only once. So, I would probably do something ling "cg gname" or something lik that. > it could be possible to tell to the server to use the cache group "prd" > to write /prod data, and the cache group "skm" to write /skim data, > avoiding the fact that the files inside the cache fs are put all together. Yes. Andy