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NMIS 8.5.6G recommends an updated and simplified directory structure for your RRD files, which is more robust and easier to deal with from an administrative perspective: all of a node's RRD database files are kept within the directory <nmisdir>/database/nodes/<nodename>. (In the past, a node's RRD files were spread across multiple directories; furthermore the directory names did include the node type, which can change under certain circumstances and which can cause all kinds of subtle inconsistencies.)
This new recommended structure is controlled by the settings in models/Common-database.nmis, and great care has been taken to make the migration from old to new layout safe and unproblematic.
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