Hi Serge! Thanks for the reply. So RRD is a FIFO. Is this a file-based DB? Looked at the docs and it says that we can define the database size at creation time. By this, if I define a size for x samples during a month, then after a month, the saved data will be overwritten with new collected data for the following month. In this situation how can I analize the flow for, e. g., 5 months? Sorry, but I'm still finding it dificult to understand the way RRDTool works as a database. Best Regards > > I'm interested in installing RRDTool on my FreeBSD box. > > I searched the web and found a nice tutorial: > > > > What type of database does RRD create? If the database is > > filled with new data and the oldest is overwritten then how > > can RRD generate a timeline graph? What's this "loop" thing? > > An RRD database is a FIFO. > You create multiple RRAs in your RRD database, they will hold > your historical data. > > Every RRA has a type (MAX, AVERAGE, ..), a size and a granularity. > For instance > - RRA 1: one sample per 5 minutes for 24 hours > - RRA 2: one sample per hour for 1 week > > Say you configured the above and you update your database every 5 > minutes. > Then after the 12th update, one hour will have passed and 12 values of > the > First RRA will be consolidated into the second. If the type of your RRAs > is > AVERAGE, the average of the 12 samples will be added to RRA 2. > The oldest 5 minutes sample will be shifted out of the first RRA and the > > oldest hourly sample will be shifted out of the second RRA. > > Serge. > > ------------- > Op de inhoud van dit e-mailbericht en de daaraan gehechte bijlagen is de inhoud van de volgende disclaimer van toepassing: http://www.zeelandnet.nl/disclaimer.php > -- Adira já ao Net Dialup Light. Acesso profissional gratuito. NovisNet, a Internet de quem trabalha. http://www.novisnet.pt -- Unsubscribe mailto:rrd-users-request@list.ee.ethz.ch?subject=unsubscribe Help mailto:rrd-users-request@list.ee.ethz.ch?subject=help Archive http://www.ee.ethz.ch/~slist/rrd-users WebAdmin http://www.ee.ethz.ch/~slist/lsg2.cgi