20021015: Setting up LDM for McIDAS-XCD (cont.)

>From: address@hidden
>Organization: UC Davis
>Keywords: 200210150109.g9F19F112387 McIDAS-XCD LDM

Hi Richard,

re:
>Erick retired about a year and a half ago...

Hmm...  it did seem like I hadn't heard from Erick in a long time.

re: OS your machine is running
>This machine is a dual pentium II 450 with 256 MB of ram running slackware
>linux 8.1.

In the past the Slackware distribution of Linux has caused some head
scratching for McIDAS and the LDM.  We'll see if the situation continues.

re: request NLDN feed from David Knight
>Okay... I'll email Dr. Knight and ask him.  I'll also email the people who
>manage my upstream feed and ask them for allow lines for the FNEXRAD and NEXRAD
>products.

I forgot to include David's email address:  address@hidden.
You will need to provide him with your machine's full name and IP address.

re: LDM version

>typo... sorry... I've been installing everything from source, and the ldm 
>version I have installed is 5.2.1. 

Sounds good.

>Ahh... another typo...  I meant the ADDE server at that point.  I think what
>I'm missing currently is that I didn't install the XCD decoders, and I'm doing
>that now...

OK.

re: sounding data

>Forgive me, I don't know what you mean by sounding data.  Is this only one
>particular data set?

Sounding data is measurements of things like Temperature, humidity, wind
speed and direction taken at different levels vertically in the atmosphere.
Meteorological data has two types of this data: measurements at mandatory
levels (e.g., surface, 925 millibars (mb), 850 mb, etc.), and measurements
at significant levels (a level is tagged as significant if the measurements
of either tempertature or winds changed significantly while moving through
that level).  The sounding server in McIDAS presents an interface to these
two different types of data making them look like one set.  Interestingly,
accessing the mandatory level and significant level data independently
causes no problems on Linux (the mandatory level ADDE dataset is
RTPTSRC/UPPERMAND; the significant ADDE dataset is RTPTSRC/UPPERSIG).

>I'd like to use this machine as the ADDE server as well,

SSEC is working on the sounding server trying to get around the weirdness
under Linux.  They thought that their latest effort had done the job, but
test I ran yesterday indicated that there were still problems.  As soon
as a solution is available, I will be making a McIDAS addendum that contains
the new code.

>but if that isn't possible, once I've got a set of working configuration files
>on my ldm/ADDE server, I can easily reinstall the operating system to another 
>unix, or use a different machine in its place.

The _only_ OS that has the remote server problem with sounding data is
Linux (all flavors, unfortunately).  The Linux guys made some sort of a
change between the 2.0.x and 2.1.x kernels that cuts off the transaction
before all data has been sent.  This is a totally weird problem that
has stymied several McIDAS developers (including myself) for quite some
time.

>Thanks for your help!

No worries.

>-- 
>THERE IS ALMOST NO LEGAL, HIGH QUALITY CONTENT AVAILABLE ON THE INTERNET. 
>                                                 -Sen. Ernest Hollings D-S.C.

What a great quote!

Tom