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20030424: atmos.uprm.edu IP Change (cont.)

>From:  Luis Munoz <address@hidden>
>Organization:  UPRM
>Keywords:  200304240323.h3O3NJ7U021069 McIDAS ADDE LDM DATALOC

Hi Luis,

>I will check into the development environment as soon as possible.
>Maybe an update to gcc will do the trick.

Thanks!  It was my hope that this kind of an upgrade would be all
that is needed.

>Our images on the webpage are
>not working.  Could it be that some of the syntax changed with this new
>version and therefore I'm not getting the information?

Since I couldn't build a new McIDAS-X distribution, nothing should have
changed in scripts that run McIDAS commands.  I was under the
impression that things were not working because no data was being
received by the LDM, and that once the LDM data reception was working
again, everything would be back to normal.  Since this is not the case,
I will have to take a closer look at what is going on.

OK, I logged onto atmos and found the problem.  By virtue of
environment variables correctly set in the 'mcidas' account, McIDAS
creates a file called /home/mcidas/data/ADDESITE.TXT that contains the
information on where McIDAS routines should look for data served by
ADDE.  One of the things that McIDAS does in this file is specify the
fully qualified name of the host by dataset group, AND also create a
line that specifies the IP address of that host.  This is done to get
around having to do a gethostbyname call each time a McIDAS command is
run.  The problem with doing this is that this essentially caches the
IP address for a host, and when the IP address of the host changes, the
name <-> IP pair information becomes incorrect.  This is exactly what
happened on atmos.  Here is the line in ADDESITE.TXT that I found when
I logged on:

HOST_ATMOS.UPRM.EDU=136.145.162.204

This is specifies that the IP address for atmos is what it used to
be.  What I did to fix this was run the following McIDAS command
as 'mcidas':

dataloc.k ADD RTIMAGES atmos.uprm.edu

This forces McIDAS to go out and do a new gethostbyname lookup and
then update ADDESITE.TXT.  Now, the line correctly reads:

HOST_ATMOS.UPRM.EDU=136.145.162.245

Given this, the McIDAS commands from the 'mcidas' account now work
correctly.  I expect that you will see the web page images get updated
as the scripts setup in 'mcidas' cron fire off.

>Since I don't have
>direct access to the machine right now I can't verify if the commands I'm
>using are the correct ones.

To use McIDAS commands while coming in from a remote machine, I just
logon as 'mcidas' and run them by hand without starting a McIDAS session.
Here is an example:

<login to atmos as 'mcidas'>
cd workdata
dsinfo.k I RTIMAGES

        Dataset Names of Type: IMAGE in Group: RTIMAGES

Name         NumPos   Content
------------ ------   --------------------------------------
ANTARCTIC       10    Antarctic IR Composite
EDFLOATER-I     10    Educational Floater
EDFLOATER-II    10    Educational Floater II
GE-IR           10    GOES-East North America IR
GE-IRTOPO       10    GOES-East IR/TOPO Composite
GE-VIS          10    GOES-East North America VIS
GE-VISTOPO      10    GOES-East VIS/TOPO Composite
GE-WV           10    GOES-East North America H2O
GEW-IR          10    GOES-East/West IR Composite
GEW-IRTOPO      10    GOES-East/West IR/TOPO Composite
GEW-VIS         10    GOES-East/West VIS Composite
GEW-VISTOPO     10    GOES-East/West VIS/TOPO Composite
GEW-WV          10    GOES-East/West H2O Composite
GW-IR           10    GOES-West Western US IR
GW-IRTOPO       10    GOES-West IR/TOPO Composite
GW-VIS          10    GOES-West Western US VIS
GW-VISTOPO      10    GOES-West VIS/TOPO Composite
GW-WV           10    GOES-West Western US H2O
MDR             10    Manually Digitized Radar
MDRTOPO         10    MDR/TOPO Composite
MOLL-IR         10    Mollweide Composite IR
MOLL-IRTOPO     10    Mollweide IR/TOPO Composite
MOLL-WV         10    Mollweide Composite H2O
RESFLOATER      10    Research Floater

DSINFO -- done

Before I ran:

dataloc.k ADD RTIMAGES atmos.uprm.edu

this command would hang and eventually time out.  Now it works correctly,
and so will others.

>Did I understand right that you can remotely
>check the data on atmos?  If so, how do you do it?

Since the remote ADDE server is setup on atmos, I can point my McIDAS
session running here in my office in Boulder at atmos:

DATALOC ADD RTIMAGES ATMOS.UPRM.EDU

Now, when I ask to look at any of the data in the dataset whose group
name is RTIMAGES, my system goes out to atmos to fulfill the request.
So, after I got the LDM back up yesterday evening, I pointed at atmos
for both RTIMAGES and RTPTSRC and then displayed satellite images
and overlayed them with surface POINT data like temperature, sea level
pressure, winds, etc.

So, if you have a machine where you can load McIDAS, you can run it
remotely and look at the data being ingested and decoded on atmos.

If you don't have a machine where you can run McIDAS -- say a fast
Windows machine --, you can download a new display and analysis package
from us called the IDV (Integrated Data Viewer).  This application
is written in Java and has the ability to look at data hosted on
ADDE and DODS servers.  It can do all of the display things that McIDAS
can do AND render 3D displays from model data.  Since it has the
capability to do 3D displays and animation, you need a fast PC that
can run Java 3D and has sufficient memory.  Windows 2000 and XP are
good candidates especially if those machines have at least 512 MB of
memory (it can have less, but runs better with more) and at least
a 1.2 Ghz processor (again, the faster the better).  For more information
on the IDV, check out:

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

Software
http://my.unidata.ucar.edu/content/software/index.html

Unidata IDV
http://my.unidata.ucar.edu/content/software/metapps/index.html

Since this application is written in Java, it can be downloaded
straight to your machine using Java Web Start and then run.  Once
you have it installed, all you will need to do to keep in touch
with atmos is setup atmos.uprm.edu as a machine with an ADDE
server to use for any of the datasets that atmos hosts (RTIMAGES,
RTPTSRC, RTWXTEXT, CIMSS).  You can also point at a number of other
servers operated in the Unidata community that host different
datasets by ADDE (e.g., GINIEAST, GINIWEST, GINICOMP, ME7, AMRC,
RTGRIDS).  This capability is the same that is provided by McIDAS,
of course.

>Thanks again,

No worries.

By the way, I just went to http://www.atmos.uprm.edu and loaded the
Latest Doppler Radar for Puerto Rico.  The image is current, so it
looks like the generation for the web is working again.

Lastly, since I can't help but poke around on systems when I help
upgrade, I took a look at the scripts being run from 'mcidas' cron.
I think that a couple of small tweaks would be useful.  For instance:

- the map drawn on top of the Latest Infrared Spectrum does not extend
  down into South America.  The script that produces this display,
  /home/mcidas/scripts/geir.sh, could be slightly changed to include
  drawing of maps over SA.

- the drawing of the maps on top of images might be better done
  as a separate invocation of MAP (map.k) rather than including
  it on the IMGDISP command line.  This way the WAIT (wait.k) could
  be removed and the display would happen a little sooner.

I would be happy to make the slight changes (and verify that my changes
don't break anything) if you like.  Please let me know.

Cheers,

Tom
--
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* Tom Yoksas                                             UCAR Unidata Program *
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