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[LDM #BUA-343681]: LDM usage

Hi Karen,

> I have a question regarding using LDM.
> 
> I've used LDM quite a lot for Level II data, NOAAPort and such, but I'm
> contemplating using it for some internal shuffling of data in a larger
> server farm we have.
> 
> Basically we have ~60 systems that need specific information from each
> other.  There are multiple algorithms and types of data and much of our
> stuff is done in discrete stages that we have spread across the servers.
> 
> Currently we are using ldm to pass intermediate products around, but
> it's a direct pass.  It's worked very well, but in order to ease
> configuration and make failovers more graceful we are considering
> setting up a couple of (redundant) servers to be "one-stop-shopping" for
> our systems.   They would only be used for sharing our data amongst
> themselves. We would still be running our main LDM server that
> request/provide data to external sources.
> 
> My concern is that we use the EXP feedtype for most of our data.  What
> I'm concerned about is that if we have a machine providing data to the
> server, and also requesting from the server, will it receive back the
> data that it has sent.  Obviously if the data is already in the queue
> ldm knows not to reinsert it, but will it be sent before or after the
> check?

The data-products will be reflected back to the originator and then discarded.

> Also, I know that even if it makes it to the queue it won't be
> written out unless there is a pqact for it.
> 
> Obviously I will craft my requests from the "central" server to be as
> specific as possible but I don't want to waste bandwidth or overload the
> systems.
> 
> I'm just hoping you can tell me what I'm considering is a reasonable use
> of LDM.

We do something similar to what you're proposing.  We have our LDM in DC send 
everything it has to our LDM in Boulder and vice versa in order to ensure that 
each has whatever the other has.  The amount of CPU and bandwidth usage due to 
this is negligible compared to everything else the LDM-s do.

Can you determine the CPU and bandwidth usage before going operational?

> -------------------------------------------
> 
> There are 2 kinds of people in the world:
> 
> 1) Those who can extrapolate from incomplete data.
> 
> -------------------------------------------
> address@hidden
> 
> Phone:  405-325-6982
> Cell: 405-834-8559
> INDUS Corporation
> National Severe Storms Laboratory

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: BUA-343681
Department: Support LDM
Priority: Normal
Status: Closed