[LDM #ONI-758666]: ldm test server

Hi Erik,

re: incorrect <hostname> in LDM registry.xml file

While an incorrect name will have no effect on the LDM's operation, it
is a good idea to fix the entry if/in case you report real-time stats
back to us.  The reason for this is that two hosts reporting real-time
statistics under the same name cause information reported to be
inaccurate, and they can even interfere with each other.

re:
> For the top tip listed here:
> https://www.unidata.ucar.edu/software/ldm/ldm-current/basics/tips.html
> 
> Do you have some instructions on commands I can run to determine the age of
> the oldest product in the queue?

Please review the info (man page or web) on 'pqmon'.  Also, it is a very
good idea to set up metrics gathering (via a pair of cron tab entries).
The reason for this is that you can then (if 'gnuplot' is installed)
run 'ldmadmin plotmetrics' to get plots of relevant metrics for your
running LDM, and one of the plots is a time series of age of the
oldest product in the LDM queue.

re:
> Also another question:
> 
> From our ldmd.conf file it looks like we have two sources listed for ANY.

Having redundant feeds of data is a good thing IF the upstreams are receiving
the same sets of data that you are REQUESTing.

re:
> In the section here
> https://www.unidata.ucar.edu/software/ldm/ldm-current/basics/configuring.html
> it this feedtype/pattern pair is either identical to that of other pairs or
> completely disjoint from them

Correct.

re:
> At the top of our list we have two ANY sources.  How do we know what
> products these two upstream servers are serving, and if they are
> identical?

If the upstream feeders are reporting real-time stats back to us, you
could compare volume plots/lists for the feed(s) you are interested
in.  If the volumes are the same, then it is _very_ likely that the
contents are the same.

You can review real-time stats being reported to us at:

Unidata HomePage
http://www.unidata.ucar.edu

  Data -> IDD Operational Status
  http://rtstats.unidata.ucar.edu/rtstats/

    Real-Time IDD Statistics -> Statistics by Host
    http://rtstats.unidata.ucar.edu/cgi-bin/rtstats/siteindex

re:
> Can we reduce CPU load/Queue load by only selecting the
> products we need vs. selecting ANY?

Yes indeed!  ANY is a compound feed type that includes all of
the feeds that you upstream site(s) are receiving.  If they
are receiving everything that is being sent in the IDD, then
they will be getting, on average, about 26 GB/hr.

NB: the LDM is very efficient in receiving/relaying products.
The major load experienced on a system running an LDM is
most typically caused by the processing that is being done
on that machine (e.g., through processing of products matched
in LDM pattern-action files).

Cheers,

Tom
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Ticket Details
===================
Ticket ID: ONI-758666
Department: Support LDM
Priority: Normal
Status: Closed
===================
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