=head1 DESCRIPTION
-RRDtool is written by Tobias Oetiker <tobi@oetiker.ch> with
+RRDtool is written by Tobias Oetiker E<lt>tobi@oetiker.chE<gt> with
contributions from many people all around the world. This document is
-written by Alex van den Bogaerdt <alex@ergens.op.het.net> to help you
+written by Alex van den Bogaerdt E<lt>alex@ergens.op.het.netE<gt> to help you
understand what RRDtool is and what it can do for you.
The documentation provided with RRDtool can be too technical for some
came with RRDtool for the location and usage of the list.
I suggest you take a moment to subscribe to the mailing list right now
-by sending an email to E<lt>rrd-users-request@list.ee.ethz.chE<gt> with a
+by sending an email to E<lt>rrd-users-request@lists.oetiker.chE<gt> with a
subject of "subscribe". If you ever want to leave this list, just write
an email to the same address but now with a subject of "unsubscribe".
=head2 What has been created?
-We created the round robin database called test (test.rrd) which
-starts at noon the day I started writing this document, 7th of March,
-1999 (this date translates to 920'804'400 seconds as explained
-below). Our database holds one data source (DS) named "speed" that
-represents a counter. This counter is read every five minutes
-(default). In the same database two round robin archives (RRAs) are
-kept, one averages the data every time it is read (e.g., there's
-nothing to average) and keeps 24 samples (24 times 5 minutes is 2
-hours). The other averages 6 values (half hour) and contains 10
-such averages (e.g., 5 hours).
+We created the round robin database called test (test.rrd) which starts at
+noon the day I started writing this document, 7th of March, 1999 (this date
+translates to 920'804'400 seconds as explained below). Our database holds
+one data source (DS) named "speed" that represents a counter. This counter
+is read every five minutes (this is the default therefore you don't have to
+put C<--step=300>). In the same database two round robin archives (RRAs)
+are kept, one averages the data every time it is read (e.g., there's nothing
+to average) and keeps 24 samples (24 times 5 minutes is 2 hours). The other
+averages 6 values (half hour) and contains 10 such averages (e.g. 5 hours).
RRDtool works with special time stamps coming from the UNIX world.
This time stamp is the number of seconds that passed since January
=head2 Updates in Reality
-We've already used the "update" command: it took one or more
+We've already used the C<update> command: it took one or more
parameters in the form of "<time>:<value>". You'll be glad to know
that you can specify the current time by filling in a "N" as the time.
Or you could use the "time" function in Perl (the shortest example in
Make sure you understand the last few paragraphs. There is no value
in only a line and a few axis, you need to know what they mean and
-interpret the data in ana appropriate way. This is true for all data.
+interpret the data in an appropriate way. This is true for all data.
The biggest mistake you can make is to use the collected data for
something that it is not suitable for. You would be better off if
You know how to create a database and can put data in it. You can get
the numbers out again by creating an image, do math on the data from
-the database and view the resulte instead of the raw data. You know
-about the difference between averages and maxima, and when to use
+the database and view the result instead of the raw data. You know
+about the difference between averages and maximum, and when to use
which (or at least you should have an idea).
RRDtool can do more than what we have learned up to now. Before you
you to be able to work with RRDtool and to read the additional
documentation available. There is plenty more to discover about
RRDtool and you will find more and more uses for this package. You can
-easly create graphs using just the examples provided and using only
+easily create graphs using just the examples provided and using only
RRDtool. You can also use one of the front ends to RRDtool that are
available.
projects / rrdtool.git / blobdiff