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Art, > I've been having occasional problems with our LDM (6.4.7.1) "resetting" > and instead of resuming data collection at the time it left off, it goes > back as far as the "-m" setting in the upstream queue. Below is an > example from yesterday with iddrs3 being the downstream node and > idd-ingest being the upstream: > > Jan 14 16:29:24 idd-ingest iddrs3.meteo.psu.edu(feed)[19268] ERROR: > Couldn't flush connection; nullproc_6() failure to iddrs3.meteo.psu.edu: > RPC: Timed out > Jan 14 16:29:46 idd-ingest iddrs3.meteo.psu.edu[19885] WARN: > findTimeEntryWithOffset(): Target data-product with given metadata not > found in time-map near its creation-time (20070114162655.320) Data-products are indexed in the product-queue according to their insertion-time and data-products have their creation-time as part of their metadata. As a consequence, it's very important that the clocks on the various LDM machines be correct. For example, if the data-product that host iddrs3 last received from host idd-ingest had a creation-time that was later than the time (according to the system clock on idd-ingest) when it was inserted into idd-ingest's product-queue, then the LDM on idd-ingest will be unable to find that last, successfully-transmitted data-product. Also, is the product-queue on idd-ingest large enough? What's the mean age of the oldest data-product? What the minimum age of the oldest product? (Use pqmon(1) to discover this.) > Jan 14 16:29:46 idd-ingest iddrs3.meteo.psu.edu[19885] NOTE: Data-product > with signature e364b6103d1b4037e788f32c5516c86b wasn't found in > product-queue > Jan 14 16:29:46 idd-ingest iddrs3.meteo.psu.edu(feed)[19885] NOTE: > Starting Up(6.4.7.1/6): 20070114102944.933 TS_ENDT {{ANY, ".*"}}, > SIG=e364b6103d1b4037e788f32c5516c86b, Primary > Jan 14 16:29:46 idd-ingest iddrs3.meteo.psu.edu(feed)[19885] NOTE: topo: > iddrs3.meteo.psu.edu {{ANY, (.*)}} > > > Jan 14 16:29:34 iddrs3 idd-ingest.meteo.psu.edu[3470] ERROR: readtcp(): > EOF on socket 4 > Jan 14 16:29:44 iddrs3 idd-ingest.meteo.psu.edu[3470] ERROR: > one_svc_run(): RPC layer closed connection > Jan 14 16:29:44 iddrs3 idd-ingest.meteo.psu.edu[3470] ERROR: Disconnecting > due to LDM failure; Connection to upstream LDM closed > Jan 14 16:29:44 iddrs3 idd-ingest.meteo.psu.edu[3470] NOTE: LDM-6 desired > product-class: 20070114102944.933 TS_ENDT {{ANY, ".*"},{NONE, > "SIG=e364b6103d1b4037e788f32c5516c86b"}} The LDM on iddrs3 is asking for data that was created about 4 hours ago. Is the maximum acceptable latency on iddrs3 really 4 hours? > Jan 14 16:29:45 iddrs3 idd-ingest.meteo.psu.edu[3470] NOTE: Upstream LDM-6 > on idd-ingest.meteo.psu.edu is willing to be a primary feeder > > Any ideas on what might be causing this? > > 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: JIG-686458 Department: Support LDM Priority: Normal Status: On Hold