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Hi Wen, re: > NCEP/NCO has been running LDM version 6.7.0 on IBM Unix machine. > > We are asking the possible solution for adding second IP address as backup > data feed so the second data feed is only activated when the primary > feed is down. There is nothing in the LDM that allows this directly. The best way to accomplish your goal is to: - create 2 ldmd.conf files: one with the REQUEST(s) to the first IP and the other with the REQUEST(s) to the second IP - create a script that is run through cron once per minute that checks to see if the LDM running at the first IP is up If it is not, the script should shutdown the ldm; swap ldmd.conf files and then restart. Comment/question: - in order to provide continuous ingest, most sites implement redundant feed REQUEST(s) in the ldmd.conf file. The connection that is getting the data the fastest will operate in PRIMARY mode (all data will be sent to it without asking if it wants each product individually) and the other will operate in SECONDARY mode (the upstream LDM will ask the downstream if it wants each product individually). If either of the connections fail, the other connection will be promoted to run in PRIMARY mode if it is not already running in PRIMARY mode. This setup is attractive since it insures delivery of products in as short a time as possible while minimizing bandwidth (in SECONDARY mode, the product is not sent before the downstream acknowledges that it wants it). Can you not use a setup like this? > Thanks, > > Wen 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: PXP-182972 Department: Support LDM Priority: Normal Status: Closed