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I have a gig of nTop RRD files and I would like to start graphing them with rrdtool (but not with nTop, since I'm hoping to do this with a separate backup of the database as workaround to the impossibility of limiting the RRD files by size), but I don't know how the files are structured.

I've tried reading the RRD documentation from SourceForge and the nTop FAQ, but I'm not finding the information I need. Does anyone know of any documentation I should be looking at or how the files are structured?

Here is a screenshot of the file structure. At first I thought it was organized by IP address (so the rrd files for address would be stored in folder 1->1->2->3 or even the reverse order), but that doesn't seem to be the case. It isn't organized by MAC address either, although some hosts are saved that way.

Any help would be appreciated.

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Have you pulled down the RRD and Ntop document from Sourceforge? I think this document should give you the context you are looking for, giving insight to the structure of the ntop file and a pretty good breakdown of rrdtool in general.

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As I stated in my question, I've read that document before and I agree it does give an excellent definition of what RRD does. There does seem to be a hint: "If ntop is monitoring an even moderately busy system there can be a huge number of hosts – many 1000s or even millions. That’s why we use the a/b/c/d subdirectory structure to limit the number of files per level in the directory structure." My problem is that I don't know what a, b, c or d is. My gut is telling me something with the IP addresses, but I can't figure it out. – Seanny123 Jul 1 '12 at 1:45

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