Hi Pavel, first of all, I am running a single node in my machine... This should not be a problem. > The way how it should work is that xrootd on redirector node pass its > prepare request to olbd and olbd keeps track of servers which are able > to prepare files (you are saying it by olb.prep directive). When the > olbd on redirector node chooses best node to serve prepare request, the > request is passed trough the olbd to that server. > The chosen server will initiate add command on its forked olb prep > command and the particular prep command should add this file into its > queue. (this is the /tmp/pre_stage.queue.0) > Problem #1 is that I don't see this queue file. A new file gets created in /tmp/prestage_log/anon/. This new file contains the filename I am willing to prestage. > Now it is a time to bring files from your tape system. So, the way how > it is done is that you need to run on each dataserver executable called > mps_PreStage. This executable needs to be started along with the xrootd > and olbd as a separate process. This executable is looking into this > /tmp/pres_stage.queue.0 and it is grabbing files one by one and > initiate this command in you configuration mps.pstg.pstgcmd. > Don't forget that you need to start mps_PreStage command with -c option > to pass the configuration file. Urgh, shall I launch mps_PreStage manually? This looks strange to me, I did not understand that. Anyway I launched it and I am keeping it running. For now, it generates no output. > > Could you please enable > > olb.trace all debug > odc.trace all debug > > in your configuration files ? So, we can see if the request is passed to > olb ? Done, but no change in the logfile with respect to before. > > Thanks > I hope I didn't confuse you Not at all, I owe a beer to you, two if I succeed! Fabrizio