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Art, > If LDM B feeds from LDM A, and LDM C feeds from LDM A and B (as primary > and secondary), should I see products on LDM C with identical product > times to those coming in on LDM B? If there's only one source for the data-products (i.e., one ingester setting the product creation-time) and the XDR layer and C runtime functions (e.g., "strftime()", "sprintf()") are working correctly, then the string representation of the product creation-time should be the same on all systems. > I've done a test case where I see > some products on C that have slightly different times than those on B... > is this an allowable occurrence or a problem? E.g. (from pqutil -v -w): > > LDM B: > Jul 03 00:00:02 pqutil INFO: 2645 20090703000000.639 HDS 596019 > SDUS84 KEPZ 022356 /pDPAHDX > > LDM C: > Jul 03 00:00:00 pqutil INFO: 2645 20090703000000.885 HDS 596019 > SDUS84 KEPZ 022356 /pDPAHDX This is a puzzle. The HDS feed comes from NOAAPORT and there are several ingesters for that data-stream. It could be that the, otherwise, identical data-products originated at different sites. > I'm investigating this because I'm trying to use this kind of > configuration for redundancy but my downstream LDM's (which would be LDM D > feeding off LDM C) is losing random data (but only sometimes) and I'm > wondering if this time variance could cause a problem. The time variance shouldn't cause a loss of data because the MD5 checksum signatures of the data products should be identical, and it's the signatures that the LDM system uses to identify data-products. > Thanks... > > Art > > Arthur A. Person > Research Assistant, System Administrator > Penn State Department of Meteorology > email: address@hidden, phone: 814-863-1563 Regards, Steve Emmerson Ticket Details =================== Ticket ID: YFA-661250 Department: Support LDM Priority: Normal Status: Closed