20040407: Vietnam and GEMPAK GRIB decoding (cont.)

>From: Mai Nguyen <address@hidden>
>Organization: National Center for Hydro-Meteorological Forecasting of Vietnam
>Keywords: 200312020023.hB20N4p2027742 IDD LDM Linux GEMPAK

Mai,

re: using chkconfig --add
>I've done what you've told me to. The last command
>didn't work. I've changed it to
>
> chkconfig --add ldmd.

You are correct.  My instructions were not complete.

>In fact, I didn't noticed the fault after some time
>since no data were coming. But now, the data is
>automatically come even after rebooting. Please check
>if it's okay.

It does not look like it worked.  chkconfig --add should
create links in the various run level directories
(/etc/rc2.d, /etc/rc3.d, etc.) to /etc/init.d/ldmd.
I don't see any of those links.

Also, I see that /etc/init.d/ldmd is not owned by root:

[ldm@met_research3 init.d]$ ls -alt ldmd
-rwxr-xr-x    1 ldm      staff        1684 Apr  6 06:22 ldmd

This script should be owned by 'root'.  I tried to use
sudo to make the change, but the account I was logged
in from is not in the sudoers file.

Here is what you should do as 'root':

cd /etc/init.d
chown root:root ldmd

You should also rerun chkconfig since the links that should
have been made were not:

chkconfig --add ldmd

After running this, you should see a file in /etc/rc5.d named
S95ldmd.  If you don't something didn't work.

>Here are some issues brought up to my mind today.
>
>1) The forecasts of the models are quite late compared
>with their base time. We normally expect the NWP
>output of 00z be available for the 06z shift, but this
>afternoon I couldn't see them even at 09z. Is that
>common for other places or it's our site's problem?

The real time statistics plots show that you are receiving
the subset of the HDS feed with latencies that are low
enough to not be causing the huge delay you mentioned.
This morning I did see that there was problem at the NWS
telecommunications gateway that was causing data to not
be sent out promptly.  I am suprised, however, that it was
over 6 hours old.  Let's keep an eye on this for the next
several days to see if the problem persists, or was tansient.

>2) I don't know how to make the meta file to be
>displayed in NTRANS. Could you please show me or
>direct me to the place that I can get the guidance.
>Thanks.

I will let our GEMPAK expert answer this one.

>3) We have some more local surface data which are not
>broadcast to the world (apart from our 25 registered
>(to WMO) stations). How can we put it in the system?
>They are the bulletins in text format. (the example
>are in /ldm/VNdata/obs, files are AAXX00, AAXX03,
>AAXX06).

I will also let our GEMPAK expert handle this one.

>4) Is it possible for us to install GEMPAK in other
>machines in our local network and look at the data
>from this computer?

Yes.

>And how can we do that?.(My first
>guess is just to mount their data to
>/nadata/ldm/gempak, but my 2nd guess is that it may
>not that simple!)

Your first guess is the correct one.  If you decide
to have other systems mount the /home/nadata/ldm
directory, then you will need to _not_ turn off NFS
as I indicated in an email earlier today.

>5) SECURITY. This is the big issue for us since we
>have virtually very little experience working with
>Linux/Unix. This computer is the first (Linux) one
>connected to the internet. So could you please advice
>us the neccesary measures to protect our computer.

I sent you a separate message on security recommendations.

>I still have many questions but have to stop here for
>now with the hope to get more of your replies ;-).

Keep the questions coming.  The more you know the more
you will be able to do with GEMPAK and the data the LDM 
is ingesting.

>Thanks Tom again.

You are welcome.

Tom
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