[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[IDD #RTY-317977]: Recent troubles with delayed 18 UTC METAR data over the IDD



Daryl,

> For the past week or so, I have been noticing a puzzling issue with ~18Z 
> METAR data (perhaps other data that I am unaware of) being delivered ~an hour 
> late or not at all.  Take for instance this product:
> 
> 20200305T191840.713081Z pqcat[17633]                pqcat.c:writeprod:80      
>           INFO        3689 20200305190516.351133 IDS|DDPLUS 27121946  SAUS80 
> KWBC 051800 RRB
> 
> So the LDM insert time is 1905z, which is an hour later than is should have 
> been.

The product was ingested (i.e., received from the NOAAPort broadcast) around 
19:05 and inserted into your product-queue around 1918 for a latency of about 
13 minutes. That is a bit much.

> The Oklahoma mesonet has a site with these files timestamped, and there it 
> appears to show some files received at the right time and others delayed
> 
> http://www.mesonet.org/data/public/noaa/text/archive/2020/03/05/18/SA/
> 
> see: 202003051800.KWBC_SAUS80_KWBC.925.txt
> vs: 202003051800.KWBC_SAUS80_KWBC.262.txt
> 
> Additonally, I have a fancy pants audit logger of the IDD and can find some 
> more detail.  Here's some telemetry for the product above for today:
> 
> SAUS80 KWBC 051800 RRB mistral.srcc.lsu.edu_v_iem-idd0.local entered LDM 
> queue at 1825z
> SAUS80 KWBC 051800 RRB leno.unidata.ucar.edu_v_iem-idd0.local entered LDM 
> queue at 1905z
> 
> and yesterday
> 
> SAUS80 KWBC 041800 RRB leno.unidata.ucar.edu_v_iem-idd0.local entered at 1850z
> SAUS80 KWBC 041800 RRB chico.unidata.ucar.edu_v_iem-idd0.local entered at 
> 1906z

It looks like the products from Unidata are arriving significantly later than 
the ones from LSU -- either that or the product was transmitted twice on 
NOAAPort and the duplicate wasn't rejected by the LDM duplicate-rejection 
mechanism.

> There are two products with different byte sizes with that same RRB header 
> (AUGH), anyway....

That would cause the duplicate-rejection mechanism to fail, so the issue could 
be due to retransmitted products that are, nevertheless, slightly different.

How different are the sizes of the products?

> So maybe the troubles are at Unidata as the LSU one was more timely?  Shrug.  
> Any known issues afoot?

No issues here that I'm aware of.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: RTY-317977
Department: Support IDD
Priority: Normal
Status: Closed
===================
NOTE: All email exchanges with Unidata User Support are recorded in the Unidata 
inquiry tracking system and then made publicly available through the web.  If 
you do not want to have your interactions made available in this way, you must 
let us know in each email you send to us.