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Hi Bongchul, re: > Thank you for your quick answers, but I have some more questions. Ready... re: > Although we requested all radar data in ldmd.conf, we are actually > getting data specified in pqact.conf which are seven radar data. You are definitely receiving all of the NEXRAD Level 2 data. This can be seen from the NEXRAD2 volume plot on our IDD statistics pages: Unidata HomePage http://www.unidata.ucar.edu Projects -> Internet Data Distribution https://www.unidata.ucar.edu/projects/index.html#idd IDD Current Operational Status https://www.unidata.ucar.edu/software/idd/rtstats/ Statistics by Host https://www.unidata.ucar.edu/cgi-bin/rtstats/siteindex s-iihr52.iihr.uiowa.edu [6.8.1] https://www.unidata.ucar.edu/cgi-bin/rtstats/siteindex?s-iihr52.iihr.uiowa.edu Part of the 'volume' plot for NEXRAD2 is a list of the sites contributing to the data you are receiving. As you will see, the list is long enough that it does not entirely fit on the plot. As to what data you are processing, this is entirely controlled by pattern-action file actions. A quick look at the pqact.conf file you sent in a previous email shows that you are, in fact, only processing a small fraction of the radars that you are receiving. re: > Can this affect our system performance (e.g., memory usage)? The receipt of large volumes of data will manifest itself in several ways: - network bandwidth use - memory use based on the size of the LDM queue - how that data is processed You are definitely using more bandwidth getting the data than your pattern-action file actions indicate that you are actively using. NB: one question needs to be answered _before_ you decide to reduce your NEXRAD2 REQUESTs: - is the data being received by s-iihr52.iihr.uiowa.edu being relayed to other machines? If yes, then you probably need to keep REQUESTing all of the data. re: > We definitely do not need all radar data since Hydro-NEXRAD is not running > now. OK, that is news to us. We were under the (perhaps incorrect) impression that all of the data was still needed/wanted. Again, Anton Kreuger should be able to speak definitively on this point. re: > Is there any way that we can modify ldmd.conf to get data from specified > radar sites in pqact.conf? Yes, this is easy to do. Here is one example of how to do this: change your existing ~ldm/etc/ldmd.conf REQUEST lines from: REQUEST NEXRAD2 ".*" idd.unidata.ucar.edu PRIMARY REQUEST NEXRAD2 ".*" idd.aos.wisc.edu ALTERNATE to: REQUEST NEXRAD2 "^L2-BZIP2/(KDVN|KDMX|KMPX|KARX|KOAX|KFSD|KEAX)" idd.unidata.ucar.edu REQUEST NEXRAD2 "(^L2-BZIP2/(KDVN|KDMX|KMPX|KARX|KOAX|KFSD|KEAX))" idd.aos.wisc.edu Comments: - the 'PRIMARY' and 'ALTERNATE' items at the end of your REQUEST lines have no meaning in current versions of the LDM (you are running v6.8.1 which ignores these qualifiers) - I surrounded the second REQUEST pattern with '()' (parentheses) to make it different from the first pattern. This is the way that REQUESTs are forced to run in primary mode in current versions of the LDM - in order to make any change made in ldmd.conf active, one has to stop and restart the LDM: <as 'ldm'> ldmadmin stop ldmadmin start OR ldmadmin restart re: > I appreciate your help. No worries. Cheers, Tom -- **************************************************************************** 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: REX-234477 Department: Support LDM Priority: Normal Status: Closed