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Hello Ulrich, Unless the file simply fails to open, it would be very difficult to ensure that a file transferred via ftp/ssh/scp/etc is 'complete'. If the transfer does not return an error indicating that the file is truncated or otherwise incomplete. Ways to verify the file you downloaded is at least a full duplicate of the remote file would be file size/history information (as you point out), or perhaps mdf5 checksums *if* the institution uses them; sadly, most do not. I believe that you are correct that the file was replaced on the remote server; I can't say that for certain, however. I'm sorry I can't provide a more positive answer; have a great day. -Ward > > Dear colleagues, > > how can I make sure that a given netcdf data set is complete? > > Recently, I got a data set (about 200 Mbytes) from NCAR-RAL by ftp. > I found that the data that were announced to be in that file were in fact not > in the file. > After some debate, I downloaded the data set again (the history information > was identical) > > The new data set was larger in bytes (factor 2.5) and now contained the > information that I was missing. > > Do you have an explanation for this? Can it happen that a data gets > transferred by ftp incomplete and such that the user does not realize this > when opening the file? > > Alternatively (and perhaps more likely), the file was changed in the ftp > server from where I downloaded. Unfortunately, I cannot check this myself. > > > Thank you, > > Ulrich Schumann > > > > -------------------------- > Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) > German Aerospace Center > Institute of Atmospheric Physics | Oberpfaffenhofen | 82234 Wessling | Germany > > Prof. Dr. Ulrich Schumann > Telephone +49 173 28 75 353 | Telefax +49 8153 28 1841 | > address@hidden<mailto:address@hidden> > www.DLR.de<http://www.dlr.de/> > > > > Ticket Details =================== Ticket ID: AIA-724598 Department: Support netCDF Priority: Normal Status: Closed