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Hi Donald, > Our switch to a "consolidated" LDM scheme is nearly complete. The > solution we implemented was to aggregate on one of four machines and > feed the other three as clients. Our train of thought is that, Should > we need to take the aggregation server off line, any of the other three > could assume the role and would have a full queue of data. This > implementation goes back to the original problem of not having enough > bandwidth for dual streams from each NEXRAD site. > > We run a series of monitoring scripts that bring down the aggregation > server and promote one of the clients to the aggregative role. This > "cut over" performed quickly & cleanly in our lab but seems somewhat > lethargic on the operational servers as we have increased the number of > NEXRAD sites.(120 of 140+ sites have been added to the system to date.) > > We have noticed that sometimes at LDM startup from client to > aggregation, ldmadmin watch doesn't show any packets being received > (although ldmping shows RESPONDING). In fact, we've waited as long as 10 > minutes without getting any data. If we delete and recreate the queue > and start again, the packets show up instantly. > > What could be causing the delay? Since deleting/re-creating the queue > doesn't show a delay, could it be related to LDM searching metadata for > 140 separate IPs? The LDM is configured to go back 1 hour, although each > location probably only has ~10 minutes worth of data. It just seems like > we are missing something if the quickest option is to delete and > recreate the queue. > > Any insight would be appreciated. What's the capacity of the product-queues at the radar sites (both in number of bytes and number of products)? > - Don > > -- > ********************************************************************** > *Donald J. Horvat * ____ * > * * / \ _____ _______ _____* > *Sr. Systems Engineer *( ) / ___ ) / ___ / / ___/* > * Support Contractor * \____/ / /__/ / / / / / / / * > *WSR-88D Radar Operations Center* |\/| / ___ < / / / / / / * > * * |/\| / / / / / /__/ / / /___ * > *1313 Halley Circle * |\/| /_/ /_/ /______/ /_____/ * > *Norman, OK 73069 * |/\| * > * * WSR-88D RADAR OPERATIONS CENTER * > ********************************************************************** > *Phone: (405) 573-3418 * e-mail: address@hidden * > *FAX: (405) 573-3340 * * > ********************************************************************** Regards, Steve Emmerson Ticket Details =================== Ticket ID: QKY-452311 Department: Support LDM Priority: Normal Status: Closed