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>From: Mai Nguyen <address@hidden> >Organization: National Center for Hydro-Meteorological Forecasting of Vietnam >Keywords: 200410040255.i942tZUE011833 LDM installation and configuration Hi Mai, >Thanks for your prompted advice. > >At the moment, our met_research3 just has been crashed >down (because of an unknown reason). So we have to >reinstall both LDM and GEMPAK. (I am truggling with >them now). Could you please resend the script ldmd >(for ldm to start when the computer starts up). re: changing upstream feed host >Sure. Please do. Do you mean you need "root" access? I >will inform you just after the computer and LDM is up. 'root' access is not needed to change the host(s) an LDM requests data from. All I needed to do (I have logged on and made the changes) was to be able to get on as the user running the LDM (user 'ldm') and make adjustments to the file ~ldm/etc/ldmd.conf. >Date: Mon, 4 Oct 2004 02:12:08 -0700 (PDT) >From: Mai Nguyen <address@hidden> >Our machine is up now, and LDM has been managed to run >somehow. However, when I start ldm, there is an error >messages: > >hupsyslog: couldn't open /var/run/syslogd.pid > >but it still runs. Is that serious? The hupsyslog error message is typically caused by either syslogd not running or the LDM application 'hupsyslog' not having setuid root permission set. >I guess there still must be some errors somewhere. >There is only nwx data coming to us. Maybe there're >some error in decoding? Do we need to create >directories for other kinds of data? (I guess ldm >created directories for nwx data. Would it do the same >for others too?) The problem turned out to be that the permissions on the HOME directory for the user 'gempak' was not readable by any user except 'gempak'. The ~ldm/etc/pqact.conf entries all include a reference to a GEMPAK table that must be read, so the entries were failing when the process couldn't read the information it needed. This caused a lot of error messages in the ~ldm/logs/ldmd.log file. The only thing I did to correct this situation was to add group and world read and execute permissions to the HOME directory for GEMPAK. In looking through the LDM-6.1.0 installation, I noticed that the standard installation had not been made. Someone had created the ~ldm/bin, ~ldm/man, ~ldm/lib, and ~ldm/include directories instead of creating a runtime link to the current LDM installation and then links to its subdirectories. The other thing I noticed was that someone had edited the ldmadmin startup script and set internal variables that are used to "point" (locate) the LDM product queue. While editing ldmadmin is done routinely (to change the queue size) it is rare to need to change the internal variables to locate the queue, etc. The best way of doing this is to make the ~ldm/data directory a link to the location where one wants data decoded and the LDM queue to reside. Given this, I removed the ~ldm/data and ~ldm/logs directories and made them links to /data/nadata and /data/nadata/logs, respectively. So, when you do a long list in the ~ldm directory now you will see various links: % ls -lt ... lrwxrwxrwx 1 ldm ldm 17 Oct 6 00:49 logs -> /home/nadata/logs lrwxrwxrwx 1 ldm ldm 12 Oct 6 00:48 data -> /home/nadata lrwxrwxrwx 1 ldm ldm 11 Oct 6 00:41 src -> runtime/src lrwxrwxrwx 1 ldm ldm 15 Oct 6 00:41 include -> runtime/include lrwxrwxrwx 1 ldm ldm 11 Oct 6 00:41 lib -> runtime/lib lrwxrwxrwx 1 ldm ldm 11 Oct 6 00:41 man -> runtime/man lrwxrwxrwx 1 ldm ldm 11 Oct 6 00:41 bin -> runtime/bin lrwxrwxrwx 1 ldm ldm 9 Oct 6 00:35 runtime -> ldm-6.1.0 ... This now looks like a "standard" LDM installation. The last thing to mention is that I had noticed that the LDM would not start up like it should on met_research3. What I mean is that it would take several minutes for the LDM to start running the processes that would ingest and then decode data. We traced this back to the LDM not being able to contact the portmapper on met_research3. We found that this was caused by the firewall running on the machine. I explicitly added an iptables entry that allows all contact to the machine from the machine: -A INPUT -s 203.162.14.98/32 -j ACCEPT (accept everything from met_research3) Now, the LDM starts up immediately after running 'ldmadmin start'. So, as I finish this note, I can say that the LDM on met_research3 appears to be running with no problems and data is getting decoded as it should where it should. The installation on met_research3 can now be used as a model for an LDM installation on other machines you may want setup. >Thanks for your helps and I am looking forward to your replies. No worries. >Best regards, Mai Cheers, Tom -- **************************************************************************** < Unidata User Support UCAR Unidata Program < (303)497-8643 P.O. Box 3000 < address@hidden Boulder, CO 80307 < ---------------------------------------------------------------------------- < Unidata WWW Service http://my.unidata.ucar.edu/content/support < ---------------------------------------------------------------------------- < NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.