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[LDM #VXF-693432]: Trying to request NEXRAD2 data from Unidata

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  • Subject: [LDM #VXF-693432]: Trying to request NEXRAD2 data from Unidata
  • Date: Mon, 01 Jul 2013 14:57:54 -0600
John,

I know why you're not getting any data: it's because the upstream LDM at out 
end is running behind. Take, for example, the previous log message

    Jul 01 20:28:29 uni19 nowcast-station-temp.mdl.nws.noa[978] INFO: sending: 
47474 20130701190115.458 NEXRAD2 499063 
L2-BZIP2/KFFC/20130701185714/499/63/I/V06/0

Note that the message was logged at 2013-07-01T20:28:29 and the product was 
created at 2013-07-01T19:01:15.458 -- more than an hour earlier! Your LDM 
discards data-products that have such a large latency.

The question is now "Why is the upstream LDM running so far behind?" This is 
most likely due to insufficient bandwidth between us, which could be caused by 
1) too low a bandwidth; 2) congestion; or 3) packet-shaping (i.e., throttling) 
of the connection between us. If it used to work, then packet-shaping is the 
likely culprit.

One way to test for packet-shaping is to request the "IDS|DDPLUS" feed. If the 
large number of small data-products in this feed get through while the larger 
NEXRAD2 products don't, then this is further evidence of packet-shaping.

> Steve,
> 
> No joy, unfortunately.  Reissuing the pqcat command yields the same result.
> 
> John
> --
> John Crockett
> Section Manager
> Science, Technology and Engineering Group
> 
> *wyle*
> *NOAA/NWS/MDL, **1325 East West Highway, Room 10302 | Silver Spring, MD
> 20910 | Phone: 301.713.0224, x112 | Fax: 301.713.9316*


Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: VXF-693432
Department: Support LDM
Priority: Normal
Status: Closed