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"Fingerhut, William A" wrote: > > Anne, > > I have finally returned, unpacked, and gotten back to work. > The workshop was really good; I learned a lot. > > When we talked about us (LSC) loosing data over 1 hour old, > I thought you said that I could use the -m flag on the > rpc.ldmd invocation. When I read the man page for rpc.ldmd > I wasn't so sure. 'skipping ahead in the queue' seems > strange? I would feel better if I understood the man page > remarks? Any chance you could help me out? > > Bill > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > < Bill Fingerhut, Professor PHONE: 802-626-6257 > > < Meteorology Dept FAX: 802-626-9770 > > < Lyndon State College > > < Lyndonville, Vt 05851 > > < > > < EMAIL: address@hidden > > < address@hidden > > < WWW: http://apollo.lsc.vsc.edu/ > > < > > < disclaimer: I know nothing - I only work here. > > vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv Hi Bill, Sorry for the delay in responding - I just returned from my vacation. And, thanks for the kind words about the workshop. It's great to hear that. I'm glad you found it helpful. Did you enjoy the rest of your vacation? The man page is confusing about the -m and the -o option to rpc.ldmd. I think the "skipping ahead in the queue" phrase refers to the case where an upstream site sends a downstream site a product that is older than the downstream site wants. In that case, the downstream site will send the upstream site a RECLASS message which will cause the upstream site to "jump forward in the queue", i.e., send the downstream site newer products because the older products are too old. In general, the -m flag specifies how old of a product you are willing to accept. I have used it to request products well over one hour old. One wrinkle is if your upstream site doesn't have products as old as you are requesting. In that case you will only get what your upstream site has. Another possibility to consider if you're going to request very old products is that your site may get swamped handling the old data and not be able to keep up locally or relay more timely data promptly. Are you a leaf node? From our site contact list it appears that Universite du Quebec a Montreal is feeding from you. Is that still accurate? In your case you probably only need to use the -m option. Just for completeness, the -o option can be used in conjunction with the -m option (but not the other way around) to limit requests to even more recent data. This is why the man page says "The value of toffset should be strickly [sic] less than max_latency." The only situation I can think of where this is useful is the one mentioned in the man page: "This may be useful when bootstraping an empty queue and you are not interested in last hour's data." I hope I've been able to shed some light on this for you. Please let me know if you have further questions. Anne -- *************************************************** Anne Wilson UCAR Unidata Program address@hidden P.O. Box 3000 Boulder, CO 80307 ---------------------------------------------------- Unidata WWW server http://www.unidata.ucar.edu/ ****************************************************