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[IDD #DQQ-790553]: Request for help with LDM setup

Hi Wesley,

> I am attempting to set up the LDM here to download data for a student-run
> weather data website.  Any help in getting the data flowing would be
> appreciated.

We will be happy to help you get things setup!

> I am working through the installation/configuration right now.

Very good.

> Information
> =================
> Site Name: University of South Alabama Weather System
> Administrator:
> Dr. Wesley Terwey
> 251-461-1389
> address@hidden
> Hostname:
> weather.southalabama.edu

OK, first thing:

There is no reverse DNS for your machine.  This can be seen by using
utilities like 'nslookup':

$ nslookup weather.southalabama.edu

Non-authoritative answer:
Name:   weather.southalabama.edu

$ nslookup

** server can't find NXDOMAIN

As you can see from this listing, there is no IP -> machine name
DNS mapping for weather.southalabama.edu.  Please work with the
networking folks at Sough Alabama to get forward AND reverse
DNS working.

The reason that this is important is the IP address of the machine
REQUESTing data (i.e., your machine) is included in the REQUEST that
is set to the upstream machine(s) (the machine(s) that will send data
to your machine).  The IP address needs to be converted into a
fully-qualified hostname (e.g., weather.southalabama.edu) before it
is matched against LDM configuration file (~ldm/etc/ldmd.conf)
ALLOW lines.

> Feed Types:
> FSL2
> =================

Some comments:

- PPS, IDS and DDS are most typically REQUESTed as 'IDS|DDPLUS':


- the combination of PPS, DDS and HDS are typically
  REQUESTed as 'WMO':


- the combination of WMO and UNIWISC can be requested as


- the FSL2 feed contains wind profiler and other data which
  can be quite voluminous

- the CONDUIT feed is _VERY_ voluminous

  Unless you have lots of bandwidth, you need to think hard
  about what portion of this data feed that you want/need.

- the LIGHTNING feeds are provided as point-to-point feeds
  by the top level sites that provide the data free-of-charge
  to the U.S. university community:

  - the NLDN lightning data is provided by UAlbany, the New York
    state University at Albany

  - the USPLN lightning data is provided by WSI Corporation

  The contact information for each of these two feeds of lightning
  data can be found in:

  Unidata HomePage

    Data -> Lightning Data

      North American Precision Lightning Network (NAPLN)

      Global Lightning Network (GLN)

      National Lightning Data Network (NLDN)

  You will need to send an email to the contacts listed in the
  last pages referenced to request a feed of lightning data.
  You should indicate in your email that you are a Unidata
  university participant.  You should also only do this _after_
  the DNS issue referenced above has been taken care of.

- like CONDUIT, the FNMOC feed can be quite voluminous, so 
  you will need to consider which products you want unless you
  have lots of bandwidth

- the NEXRAD2 datastream is also quite voluminous; the same
  comment made for CONDUIT and FNMOC applies to it

- NEXRAD3 contains NEXRAD Level III products for all NEXRADs
  delivered in the NOAAPort Satellite Broadcast Network (SBN)

  This feed is also voluminous and has lots of products.  Some
  sites have problems ingesting and processing (typically
  filing to disk) all of the products available in NEXRAD3.

For reference, here is a snapshot of the volumes in the various
datastreams that are delivered by the IDD:

Data Volume Summary for  idd.unidata.ucar.edu

Maximum hourly volume  23164.623 M bytes/hour
Average hourly volume  15072.076 M bytes/hour

Average products per hour     330226 prods/hour

Feed                           Average             Maximum     Products
                     (M byte/hour)            (M byte/hour)   number/hour
NEXRAD2                5260.667    [ 34.903%]     6978.108    73109.065
CONDUIT                3495.363    [ 23.191%]     5490.003    73157.109
NEXRAD3                1889.778    [ 12.538%]     2409.144    98601.239
FSL2                   1520.290    [ 10.087%]     1883.157     1659.674
NGRID                  1123.644    [  7.455%]     2149.776    20112.565
FNMOC                   980.239    [  6.504%]     6781.229     2802.478
HDS                     327.107    [  2.170%]      615.243    17547.065
NIMAGE                  196.234    [  1.302%]      409.064      214.783
GEM                      82.142    [  0.545%]      518.345      935.130
FNEXRAD                  70.018    [  0.465%]       88.544       70.870
IDS|DDPLUS               49.940    [  0.331%]       70.068    41247.283
EXP                      41.478    [  0.275%]       81.956      393.804
UNIWISC                  23.499    [  0.156%]       33.841       21.609
LIGHTNING                 8.160    [  0.054%]       23.377      346.935
DIFAX                     3.367    [  0.022%]       12.044        5.043
GPS                       0.148    [  0.001%]        1.478        1.065

> Thank you very much for your help.

No worries.  Please let us know when the LDM has been installed on
weather.southalabama.edu AND the DNS for that machine is fixed.  At that
point we will assign you one or more hosts from which you can REQUEST
the types of data that you desire.

Last question:

- how will you be processing the data when you receive it?

  What I mean is are you going to be using a Unidata-supplied package
  like GEMPAK or McIDAS to visualize/analyze the data, and, if yes,
  are you enough familiar with that package to know that it has
  default LDM configuration settings to decode the data into formats
  it can use?

  Or, are you planning on "rolling your own"?


Unidata User Support                                    UCAR Unidata Program
(303) 497-8642                                                 P.O. Box 3000
address@hidden                                   Boulder, CO 80307
Unidata HomePage                       http://www.unidata.ucar.edu

Ticket Details
Ticket ID: DQQ-790553
Department: Support IDD
Priority: Normal
Status: Closed