This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.
Sue, > No worries. I think I may have it figured out. I think the checksum > signature for "unique" products is the same. We are transferring files > from our research system and from our operational system through the > same LDM gateway servers. The product id's are unique but similar. Whew! I'm glad to hear that it's probably not the LDM's fault. :-) > ldmd.log:Jun 21 08:38:19 salt cospa3.rap.ucar.edu[11360] INFO: > d9de5af0dc90916b21c4702136fb3ed5 62225 20120621143756.657 EXP > 000 > ncar.ral.CoSPA.Shadow.BlendNcarPcEchoTops.2012-06-21T14:30:00.PT02:15.nc > > ldmd.log:Jun 21 08:38:51 salt cospa9.rap.ucar.edu[11359] INFO: hereis: > duplicate: d9de5af0dc90916b21c4702136fb3ed5 62225 > 20120621143844.913 EXP 000 > ncar.ral.CoSPA.Live.BlendNcarPcEchoTops.2012-06-21T14:30:00.PT02:15.nc Those two data-products do have the same signature, so the product-queue will reject the second one as being a duplicate. > I am not sure how the checksum is computed but I will look at that. Typically, the signature is the MD5 checksum of the contents of the data-product. > Does this seem reasonable? How can we insure unique signatures for our > products. If you're using pqinsert(1) to insert the data-products into an LDM product-queue, then, by default, the signature will be computed as the MD5 checksum of the contents of the file. The "-i" option will cause the signature to be computed as the MD5 checksum of the product-identifier, so if the identifiers are unique, then so will the signatures. > Thanks, > Sue Regards, Steve Emmerson Ticket Details =================== Ticket ID: OFP-197738 Department: Support LDM Priority: Normal Status: Closed