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Re: 20020416: LDM dropping some suominet data

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  • Subject: Re: 20020416: LDM dropping some suominet data
  • Date: Tue, 16 Apr 2002 14:53:59 -0600 (MDT)
Teresa, 

The way the LDM is designed is to try and keep current.

So, if all sites are reporting (ingesting) data at :05 after the hour, all
on the gpssrc (AFOS) feedtype, the LDM will begin looking for data after
the time the last successful gpssrc feed came in. So unless ALL sites
failed to transmit, the LDM is assuming it has gpssrc data from that time
and looks into the time ahead for products. A fix would be to assign each
site a feedtype, but we do not have that many. Another option is to
determine what site (s) are problematic with network connections and have
them either ingest at different times, or use other transfer protocols
(SCP,FTP, etc) and not let the LDM get spoofed into thinking it has the
data.

If the downed site was the only one feeding gpssrc, the -o -m flags would 
work and allow you to get the older products..

Are we seeing certain problematic sites?

Is there any periodicity?

Thanks,

-Jeff
____________________________                  _____________________
Jeff Weber                                    address@hidden
Unidata Support                               PH:303-497-8676 
NWS-COMET Case Study Library                  FX:303-497-8690
University Corp for Atmospheric Research      3300 Mitchell Ln
http://www.unidata.ucar.edu/staff/jweber      Boulder,Co 80307-3000
________________________________________      ______________________

On Tue, 16 Apr 2002, Unidata Support wrote:

> 
> ------- Forwarded Message
> 
> >To: "address@hidden" <address@hidden>,
> >To: Doug Hunt <address@hidden>
> >From: Teresa Van Hove <address@hidden>
> >Subject: LDM dropping some suominet data
> >Organization: GST
> >Keywords: 200204161648.g3GGm4a17036
> 
> 
> LDM is dropping some of our suominet data.  It seems that if a file was
> being sent and the send is not completed it just quits trying after an
> hour, and when the connection is better the next hour or two I don't get
> the file, which I would if the file was 'new' to my ldm since I have my
> -o and -m flags set for 129000 seconds to get data that is over 24 hours
> old.
> 
> Is there a flag I can set to change this behavior?  Jeff suggested that
> my cpu may not have enough ram for the # of sites that are sending data,
> do you have some guidelines on what cpu capacities are needed for
> various #'s of ldm connections and data loads?    Also if this is simply
> a matter of too many processes perhaps its going to be neccessary to
> have some topology rather than connecting to every suominet site for
> data as well as allowing every site that requests data to connect to my
> ldm box.
> 
> Thanks,
> 
> Teresa
> 
> 
> ------- End of Forwarded Message
> 
>