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Dear Xrootd Gurus, As you know, we are trying to evaluate xrootd to see if it does what we need. We have some questions that may speed along our understanding. 1. When a request is made for a file that has to be staged from an HSM server, we would like to get back either: a) an estimate of how long it will be before the file is ready for reading, or b) a least a bit indicating that this request will wait for staging. Is this possible without "major" changes? The "prepare" request looks like it has space for an arbitrary response, but it isn't clear to me from the protocol description how arbitrary it really is. It may be that open needs to send back an indicator as well, but that may be harder. 2. Is there a way to pin a file once it has been staged to a disk server, so that it is not a candidate for removal from the server? If so, is this done on a per-file basis, and/or a per-directory basis? 3. Is there anyway a file can be dropped from a disk server while a client has it "open"? If so, will subsequent access attempts result in a new redirect or recache attempt? 4. Does xrootd automatically replicate a file to an additional server if demand for that file gets too high for a single server to sustain? All that I've read suggests that it does, but I'm having a little trouble tracking down the code that does the work. Many thanks for your assistance. -- Gregory J. Sharp email: [log in to unmask] Wilson Synchrotron Laboratory url: http://www.lepp.cornell.edu/~gregor Dryden Rd ph: +1 607 255 4882 Ithaca, NY 14853 fax: +1 607 255 8062