Tribblix: manual page: rrdgraph.1

RRDGRAPH(1) rrdtool RRDGRAPH(1)

NAME

rrdgraph - Round Robin Database tool graphing functions

SYNOPSIS

rrdtool graph|graphv filename [option ...] [data definition ...]
[data calculation ...] [variable definition ...] [graph element ...]
[print element ...]

DESCRIPTION

The graph function of RRDtool is used to present the data from an RRD
to a human viewer. Its main purpose is to create a nice graphical
representation, but it can also generate a numerical report.

OVERVIEW

rrdtool graph needs data to work with, so you must use one or more
data definition statements to collect this data. You are not limited
to one database, it's perfectly legal to collect data from two or
more databases (one per statement, though).

If you want to display averages, maxima, percentiles, etcetera it is
best to collect them now using the variable definition statement.
Currently this makes no difference, but in a future version of
RRDtool you may want to collect these values before consolidation.

The data fetched from the RRA is then consolidated so that there is
exactly one data point per pixel in the graph. If you do not take
care yourself, RRDtool will expand the range slightly if necessary.
Note, in that case the first and/or last pixel may very well become
unknown!

Sometimes data is not exactly in the format you would like to display
it. For instance, you might be collecting bytes per second, but want
to display bits per second. This is what the data calculation command
is designed for. After consolidating the data, a copy is made and
this copy is modified using a rather powerful RPN command set.

When you are done fetching and processing the data, it is time to
graph it (or print it). This ends the rrdtool graph sequence.

Use graphv instead of graph to get detailed information about the
graph geometry and data once it is drawn. See the bottom of the
document for more information.

OPTIONS

filename
The name and path of the graph to generate. It is recommended to end
this in ".png", ".svg" or ".eps", but RRDtool does not enforce this.

filename can be '"-"' to send the image to "stdout". In this case, no
other output is generated.

Time range

[-s|--start time] [-e|--end time] [-S|--step seconds]

The start and end of the time series you would like to display, and
which RRA the data should come from. Defaults are: 1 day ago until
now, with the best possible resolution. Start and end can be
specified in several formats, see "AT-STYLE TIME SPECIFICATION" in
rrdfetch and rrdgraph_examples. By default, rrdtool graph calculates
the width of one pixel in the time domain and tries to get data from
an RRA with that resolution. With the step option you can alter this
behavior. If you want rrdtool graph to get data at a one-hour
resolution from the RRD, set step to 3'600. Note: a step smaller than
one pixel will silently be ignored.

For non-image --imgformats see "OUTPUT FORMAT" in rrdxport for
details on how this affects the output.

Labels

[-t|--title string]

A horizontal string placed at the top of the graph which may be
separated into multiple lines using or \n

[-v|--vertical-label string]

A vertical string placed at the left hand of the graph.

Size

[-w|--width pixels] [-h|--height pixels] [-j|--only-graph]
[-D|--full-size-mode]

By default, the width and height of the canvas (the part with the
actual data and such). This defaults to 400 pixels by 100 pixels.

If you specify the --full-size-mode option, the width and height
specify the final dimensions of the output image and the canvas is
automatically resized to fit.

If you specify the --only-graph option and set the height < 32 pixels
you will get a tiny graph image (thumbnail) to use as an icon for use
in an overview, for example. All labeling will be stripped off the
graph.

Limits

[-u|--upper-limit value] [-l|--lower-limit value] [-r|--rigid]
[--allow-shrink]

By default the graph will be autoscaling so that it will adjust the
y-axis to the range of the data. You can change this behavior by
explicitly setting the limits. The displayed y-axis will then range
at least from lower-limit to upper-limit. Autoscaling will still
permit those boundaries to be stretched unless the rigid option is
set. allow-shrink alters behavior of rigid by allowing auto down
scale, graph will not overrun user specified limits.

[-A|--alt-autoscale]

Sometimes the default algorithm for selecting the y-axis scale is not
satisfactory. Normally the scale is selected from a predefined set of
ranges and this fails miserably when you need to graph something like
"260 + 0.001 * sin(x)". This option calculates the minimum and
maximum y-axis from the actual minimum and maximum data values. Our
example would display slightly less than "260-0.001" to slightly more
than "260+0.001" (this feature was contributed by Sasha Mikheev).

[-J|--alt-autoscale-min]

Where "--alt-autoscale" will modify both the absolute maximum AND
minimum values, this option will only affect the minimum value. The
maximum value, if not defined on the command line, will be 0. This
option can be useful when graphing router traffic when the WAN line
uses compression, and thus the throughput may be higher than the WAN
line speed.

[-M|--alt-autoscale-max]

Where "--alt-autoscale" will modify both the absolute maximum AND
minimum values, this option will only affect the maximum value. The
minimum value, if not defined on the command line, will be 0. This
option can be useful when graphing router traffic when the WAN line
uses compression, and thus the throughput may be higher than the WAN
line speed.

[-N|--no-gridfit]

In order to avoid anti-aliasing blurring effects RRDtool snaps points
to device resolution pixels, this results in a crisper appearance. If
this is not to your liking, you can use this switch to turn this
behavior off.

Grid-fitting is turned off for PDF, EPS, SVG output by default.

X-Axis
[-x|--x-grid GTM:GST:MTM:MST:LTM:LST:LPR:LFM]

[-x|--x-grid none]

The x-axis label is quite complex to configure. If you don't have
very special needs it is probably best to rely on the auto
configuration to get this right. You can specify the string "none" to
suppress the grid and labels altogether.

The grid is defined by specifying a certain amount of time in the ?TM
positions. You can choose from "SECOND", "MINUTE", "HOUR", "DAY",
"WEEK", "MONTH" or "YEAR". Then you define how many of these should
pass between each line or label. This pair (?TM:?ST) needs to be
specified for the base grid (G??), the major grid (M??) and the
labels (L??). For the labels you also must define a precision in LPR
and a strftime format string in LFM. LPR defines where each label
will be placed. If it is zero, the label will be placed right under
the corresponding line (useful for hours, dates etcetera). If you
specify a number of seconds here the label is centered on this
interval (useful for Monday, January etcetera).

--x-grid MINUTE:10:HOUR:1:HOUR:4:0:%X

This places grid lines every 10 minutes, major grid lines every hour,
and labels every 4 hours. The labels are placed under the major grid
lines as they specify exactly that time.

--x-grid HOUR:8:DAY:1:DAY:1:86400:%A

This places grid lines every 8 hours, major grid lines and labels
each day. The labels are placed exactly between two major grid lines
as they specify the complete day and not just midnight.

[--week-fmt strftime format string]

By default rrdtool uses "Week %V" to render the week number. With
this option you can define your own format, without completely
overriding the xaxis format.

Y-Axis
[-y|--y-grid grid step:label factor]

[-y|--y-grid none]

Y-axis grid lines appear at each grid step interval. Labels are
placed every label factor lines. You can specify "-y none" to
suppress the grid and labels altogether. The default for this option
is to automatically select sensible values.

If you have set --y-grid to 'none' not only the labels get
suppressed, also the space reserved for the labels is removed. You
can still add space manually if you use the --units-length command to
explicitly reserve space.

[--left-axis-formatter formatter-name]

Specify what formatter to use to render axis values.

numeric
The default, values are expressed as numeric quantities.

timestamp
Values are interpreted as unix timestamps (number of seconds
since 1970-01-01 00:00:00 UTC) and expressed using strftime
format (default is '%Y-%m-%d %H:%M:%S'). See also --units-length
and --left-axis-format.

duration
Values are interpreted as duration in milliseconds. Formatting
follows the rules of valstrfduration qualified PRINT/GPRINT. See
rrdgraph_graph.

[--left-axis-format format-string]

By default the format of the axis labels gets determined
automatically. If you want to do this yourself, use this option with
the same %lf arguments you know from the PRINT and GPRINT commands,
or others if using different formatter.

[-Y|--alt-y-grid]

Place the Y grid dynamically based on the graph's Y range. The
algorithm ensures that you always have a grid, that there are enough
but not too many grid lines, and that the grid is metric. That is the
grid lines are placed every 1, 2, 5 or 10 units. This parameter will
also ensure that you get enough decimals displayed even if your graph
goes from 69.998 to 70.001. (contributed by Sasha Mikheev).

[-o|--logarithmic]

Logarithmic y-axis scaling.

[-X|--units-exponent value]

This sets the 10**exponent scaling of the y-axis values. Normally,
values will be scaled to the appropriate units (k, M, etc.).
However, you may wish to display units always in k (Kilo, 10e3) even
if the data is in the M (Mega, 10e6) range, for instance. Value
should be an integer which is a multiple of 3 between -18 and 18
inclusively. It is the exponent on the units you wish to use. For
example, use 3 to display the y-axis values in k (Kilo, 10e3,
thousands), use -6 to display the y-axis values in u (Micro, 10e-6,
millionths). Use a value of 0 to prevent any scaling of the y-axis
values.

This option is very effective at confusing the heck out of the
default RRDtool autoscaling function and grid painter. If RRDtool
detects that it is not successful in labeling the graph under the
given circumstances, it will switch to the more robust --alt-y-grid
mode.

[-L|--units-length value]

How many digits should RRDtool assume the y-axis labels to be? You
may have to use this option to make enough space once you start
fiddling with the y-axis labeling.

[--units=si]

With this option y-axis values on logarithmic graphs will be scaled
to the appropriate units (k, M, etc.) instead of using exponential
notation. Note that for linear graphs, SI notation is used by
default.

Right Y Axis

[--right-axis scale:shift] [--right-axis-label label]

A second axis will be drawn to the right of the graph. It is tied to
the left axis via the scale and shift parameters. You can also define
a label for the right axis.

[--right-axis-formatter formatter-name]

Specify what formatter to use to render axis values.

numeric
The default, values are expressed as numeric quantities.

timestamp
Values are interpreted as unix timestamps (number of seconds
since 1970-01-01 00:00:00 UTC) and expressed using strftime
format (default is '%Y-%m-%d %H:%M:%S'). See also --units-length
and --right-axis-format.

duration
Values are interpreted as duration in milliseconds. Formatting
follows the rules of valstrfduration qualified PRINT/GPRINT. See
rrdgraph_graph.

[--right-axis-format format-string]

By default the format of the axis labels gets determined
automatically. If you want to do this yourself, use this option with
the same %lf arguments you know from the PRINT and GPRINT commands,
or others if using different formatter.

Legend

[-g|--no-legend]

Suppress generation of the legend; only render the graph.

[-F|--force-rules-legend]

Force the generation of HRULE and VRULE legends even if those HRULE
or VRULE will not be drawn because out of graph boundaries (mimics
behavior of pre 1.0.42 versions).

[--legend-position=(north|south|west|east)]

Place the legend at the given side of the graph. The default is
south. In west or east position it is necessary to add line breaks
manually.

[--legend-direction=(topdown|bottomup|bottomup2)]

Place the legend items in the given vertical order. The default is
topdown. Using bottomup the legend items appear in the same vertical
order as a stack of lines or areas. Using bottomup2 will keep leading
and trailing COMMENT lines in order, this might be useful for
generators that use them for table headers and the like.

Miscellaneous

[-z|--lazy]

Only generate the graph if the current graph is out of date or not
existent. Note, that all the calculations will happen regardless so
that the output of PRINT and graphv will be complete regardless. Note
that the behavior of lazy in this regard has seen several changes
over time. The only thing you can really rely on before RRDtool 1.3.7
is that lazy will not generate the graph when it is already there and
up to date, and also that it will output the size of the graph.

[-d|--daemon address]

Address of the rrdcached daemon. If specified, a "flush" command is
sent to the server before reading the RRD files. This allows the
graph to contain fresh data even if the daemon is configured to cache
values for a long time. For a list of accepted formats, see the -l
option in the rrdcached manual.

rrdtool graph [...] --daemon unix:/var/run/rrdcached.sock [...]

[-f|--imginfo printfstr]

After the image has been created, the graph function uses printf
together with this format string to create output similar to the
PRINT function, only that the printf function is supplied with the
parameters filename, xsize and ysize. In order to generate an IMG tag
suitable for including the graph into a web page, the command line
would look like this:

--imginfo '<IMG SRC="/img/%s" WIDTH="%lu" HEIGHT="%lu" ALT="Demo">'

[-c|--color COLORTAG#rrggbb[aa]]

Override the default colors for the standard elements of the graph.
The COLORTAG is one of "BACK" background, "CANVAS" for the background
of the actual graph, "SHADEA" for the left and top border, "SHADEB"
for the right and bottom border, "GRID", "MGRID" for the major grid,
"FONT" for the color of the font, "AXIS" for the axis of the graph,
"FRAME" for the line around the color spots, and finally "ARROW" for
the arrow head pointing up and forward. Each color is composed out of
three hexadecimal numbers specifying its rgb color component (00 is
off, FF is maximum) of red, green and blue. Optionally you may add
another hexadecimal number specifying the transparency (FF is solid).
You may set this option several times to alter multiple defaults.

A green arrow is made by: "--color ARROW#00FF00"

[--grid-dash on:off]

by default the grid is drawn in a 1 on, 1 off pattern. With this
option you can set this yourself

--grid-dash 1:3 for a dot grid

--grid-dash 1:0 for uninterrupted grid lines

[--border width]

Width in pixels for the 3d border drawn around the image. Default 2,
0 disables the border. See "SHADEA" and "SHADEB" above for setting
the border color.

[--dynamic-labels]

Pick the shape of the color marker next to the label according to the
element drawn on the graph.

[-m|--zoom factor]

Zoom the graphics by the given amount. The factor must be > 0

[-n|--font FONTTAG:size[:font]]

This lets you customize which font to use for the various text
elements on the RRD graphs. "DEFAULT" sets the default value for all
elements, "TITLE" for the title, "AXIS" for the axis labels, "UNIT"
for the vertical unit label, "LEGEND" for the graph legend,
"WATERMARK" for the watermark on the edge of the graph.

Use Times for the title: "--font TITLE:13:Times"

Note that you need to quote the argument to --font if the font-name
contains whitespace: --font "TITLE:13:Some Font"

If you do not give a font string you can modify just the size of the
default font: "--font TITLE:13:".

If you specify the size 0 then you can modify just the font without
touching the size. This is especially useful for altering the default
font without resetting the default fontsizes: "--font
DEFAULT:0:Courier".

RRDtool comes with a preset default font. You can set the environment
variable "RRD_DEFAULT_FONT" if you want to change this.

RRDtool uses Pango for its font handling. This means you can to use
the full Pango syntax when selecting your font:

The font name has the form "[FAMILY-LIST] [STYLE-OPTIONS] [SIZE]",
where FAMILY-LIST is a comma separated list of families optionally
terminated by a comma, STYLE_OPTIONS is a whitespace separated list
of words where each WORD describes one of style, variant, weight,
stretch, or gravity, and SIZE is a decimal number (size in points) or
optionally followed by the unit modifier "px" for absolute size. Any
one of the options may be absent.

[-R|--font-render-mode {normal,light,mono}]

There are 3 font render modes:

normal: Full Hinting and Anti-aliasing (default)

light: Slight Hinting and Anti-aliasing

mono: Full Hinting and NO Anti-aliasing

[-B|--font-smoothing-threshold size]

(this gets ignored in 1.3 for now!)

This specifies the largest font size which will be rendered
bitmapped, that is, without any font smoothing. By default, no text
is rendered bitmapped.

[-P|--pango-markup]

All text in RRDtool is rendered using Pango. With the --pango-markup
option, all text will be processed by pango markup. This allows one
to embed some simple html like markup tags using

text

Apart from the verbose syntax, there are also the following short
tags available.

b Bold
big Makes font relatively larger, equivalent to 
i Italic
s Strikethrough
sub Subscript
sup Superscript
small Makes font relatively smaller, equivalent to 
tt Monospace font
u Underline

More details on
<http://developer.gnome.org/pango/stable/PangoMarkupFormat.html>.

[-G|--graph-render-mode {normal,mono}]

There are 2 render modes:

normal: Graphs are fully Anti-aliased (default)

mono: No Anti-aliasing

[-E|--slope-mode]

RRDtool graphs are composed of stair case curves by default. This is
in line with the way RRDtool calculates its data. Some people favor a
more 'organic' look for their graphs even though it is not all that
true.

[-a|--imgformat
PNG|SVG|EPS|PDF|XML|XMLENUM|JSON|JSONTIME|CSV|TSV|SSV]

Image format for the generated graph. For the vector formats you can
choose among the standard Postscript fonts Courier-Bold, Courier-
BoldOblique, Courier-Oblique, Courier, Helvetica-Bold, Helvetica-
BoldOblique, Helvetica-Oblique, Helvetica, Symbol, Times-Bold, Times-
BoldItalic, Times-Italic, Times-Roman, and ZapfDingbats.

For Export type you can define XML, XMLENUM (enumerates the value
tags <v0>,<v1>,<v2>,...), JSON, JSONTIME (adds a timestamp to each
data row), CSV (=comma separated values), TSV (=tab separated
values), SSV (=semicolon separated values), (for comma/tab/semicolon
separated values the time format by default is in the form of unix
time. to change it to something else use: --x-grid
MINUTE:10:HOUR:1:HOUR:4:0:"%Y-%m-%d %H:%M:%S")

For non-image --imgformats see "OUTPUT FORMAT" in rrdxport for
details on the output.

[-i|--interlaced]

(this gets ignored in 1.3 for now!)

If images are interlaced they become visible on browsers more
quickly.

[-T|--tabwidth value]

By default the tab-width is 40 pixels, use this option to change it.

[-b|--base value]

If you are graphing memory (and NOT network traffic) this switch
should be set to 1024 so that one Kb is 1024 byte. For traffic
measurement, 1 kb/s is 1000 b/s.

[-W|--watermark string]

Adds the given string as a watermark, horizontally centered, at the
bottom of the graph.

[-Z|--use-nan-for-all-missing-data]

If one DS is missing, either because the RRD is not available or
because it does not contain the requested DS name, just assume that
we got empty values instead of raising a fatal error.

[--add-jsontime]

Adds xport data in JSONTIME format, giving both graph image data and
data point values in one call to graphv command.

[--utc]

Force the timezone to be UTC. Equivalent to doing TZ=UTC rrdtool
graph .... This is useful to calculate daily average ranging from
midnight to midnight rather than say the last 24 hours.

Data and variables

DEF:vname=rrdfile:ds-name:CF[:step=step][:start=time][:end=time]

CDEF:vname=RPN expression

VDEF:vname=RPN expression

You need at least one DEF and one LINE, AREA, GPRINT, PRINT statement
to generate anything useful.

See rrdgraph_data and rrdgraph_rpn for the exact format.

NOTE: Graph and print elements

You need at least one graph element to generate an image and/or at
least one print statement to generate a report. See rrdgraph_graph
for the exact format.

graphv
Calling RRDtool with the graphv option will return information in the
RRDtool info format. On the command line this means that all output
will be in key=value format. When used from the Perl and Ruby
bindings a hash pointer will be returned from the call.

When the filename '-' is given, the contents of the graph itself will
also be returned through this interface (hash key 'image'). On the
command line the output will look like this:

print[0] = "0.020833"
print[1] = "0.0440833"
graph_left = 51
graph_top = 22
graph_width = 400
graph_height = 100
graph_start = 1232908800
graph_end = 1232914200
image_width = 481
image_height = 154
value_min = 0.0000000000e+00
value_max = 4.0000000000e-02
image = BLOB_SIZE:8196
[... 8196 bytes of image data ...]

There is more information returned than in the standard interface.
Especially the 'graph_*' keys are new. They help applications that
want to know what is where on the graph.

ENVIRONMENT VARIABLES

The following environment variables may be used to change the
behavior of "rrdtool graph":

RRDCACHED_ADDRESS
If this environment variable is set it will have the same effect
as specifying the "--daemon" option on the command line. If both
are present, the command line argument takes precedence.

RRD_DEFAULT_FONT
RRDtool comes with a preset default font. You can set the
environment variable RRD_DEFAULT_FONT if you want to change this.

AUTHOR

Program by Tobias Oetiker <tobi@oetiker.ch>

This manual page by Alex van den Bogaerdt <alex@vandenbogaerdt.nl>
with corrections and/or additions by several people

1.8.0 2022-03-14 RRDGRAPH(1)