RRDGRAPH(1)                         rrdtool                        RRDGRAPH(1)



NNAAMMEE
       rrdgraph - Round Robin Database tool graphing functions

SSYYNNOOPPSSIISS
       rrrrddttooooll ggrraapphh||ggrraapphhvv _f_i_l_e_n_a_m_e [_o_p_t_i_o_n ...]  [_d_a_t_a _d_e_f_i_n_i_t_i_o_n ...]
       [_d_a_t_a _c_a_l_c_u_l_a_t_i_o_n ...]  [_v_a_r_i_a_b_l_e _d_e_f_i_n_i_t_i_o_n ...]  [_g_r_a_p_h _e_l_e_m_e_n_t ...]
       [_p_r_i_n_t _e_l_e_m_e_n_t ...]

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

OOVVEERRVVIIEEWW
       rrrrddttooooll ggrraapphh needs data to work with, so you must use one or more ddaattaa
       ddeeffiinniittiioonn 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 vvaarriiaabbllee ddeeffiinniittiioonn 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 RRRRAA is then ccoonnssoolliiddaatteedd so that there is
       exactly one data point per pixel in the graph. If you do not take care
       yourself, RRRRDDttooooll 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 bbyytteess per second, but want to
       display bbiittss per second. This is what the ddaattaa ccaallccuullaattiioonn command is
       designed for. After ccoonnssoolliiddaattiinngg the data, a copy is made and this
       copy is modified using a rather powerful RRPPNN command set.

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

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

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

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

   TTiimmee rraannggee
       [--ss|----ssttaarrtt _t_i_m_e] [--ee|----eenndd _t_i_m_e] [--SS|----sstteepp _s_e_c_o_n_d_s]

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

   LLaabbeellss
       [--tt|----ttiittllee _s_t_r_i_n_g] [--vv|----vveerrttiiccaall--llaabbeell _s_t_r_i_n_g]

       A horizontal string at the top of the graph and/or a vertically placed
       string at the left hand side of the graph.

   SSiizzee
       [--ww|----wwiiddtthh _p_i_x_e_l_s] [--hh|----hheeiigghhtt _p_i_x_e_l_s] [--jj|----oonnllyy--ggrraapphh]
       [--DD|----ffuullll--ssiizzee--mmooddee]

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

       If you specify the ----ffuullll--ssiizzee--mmooddee 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 ----oonnllyy--ggrraapphh 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.

   LLiimmiittss
       [--uu|----uuppppeerr--lliimmiitt _v_a_l_u_e] [--ll|----lloowweerr--lliimmiitt _v_a_l_u_e] [--rr|----rriiggiidd]

       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 lloowweerr--lliimmiitt to uuppppeerr--lliimmiitt. Autoscaling will still permit
       those boundaries to be stretched unless the rriiggiidd option is set.

       [--AA|----aalltt--aauuttoossccaallee]

       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).

       [--JJ|----aalltt--aauuttoossccaallee--mmiinn]

       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.

       [--MM|----aalltt--aauuttoossccaallee--mmaaxx]

       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.

       [--NN|----nnoo--ggrriiddffiitt]

       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.

   XX--AAxxiiss
       [--xx|----xx--ggrriidd _G_T_M::_G_S_T::_M_T_M::_M_S_T::_L_T_M::_L_S_T::_L_P_R::_L_F_M]

       [--xx|----xx--ggrriidd nnoonnee]

       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 _?_T_M
       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 (_?_T_M_:_?_S_T) 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 _L_P_R and a
       _s_t_r_f_t_i_m_e format string in _L_F_M.  _L_P_R 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.

       [----wweeeekk--ffmmtt _s_t_r_f_t_i_m_e _f_o_r_m_a_t _s_t_r_i_n_g]

       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.

   YY--AAxxiiss
       [--yy|----yy--ggrriidd _g_r_i_d _s_t_e_p::_l_a_b_e_l _f_a_c_t_o_r]

       [--yy|----yy--ggrriidd nnoonnee]

       Y-axis grid lines appear at each _g_r_i_d _s_t_e_p interval.  Labels are placed
       every _l_a_b_e_l _f_a_c_t_o_r 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.

       [----lleefftt--aaxxiiss--ffoorrmmaatttteerr _f_o_r_m_a_t_t_e_r_-_n_a_m_e]

       Specify what formatter to use to render axis values.

       nnuummeerriicc
           The default, values are expressed as numeric quantities.

       ttiimmeessttaammpp
           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 ----uunniittss--lleennggtthh and
           ----lleefftt--aaxxiiss--ffoorrmmaatt.

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

       [----lleefftt--aaxxiiss--ffoorrmmaatt _f_o_r_m_a_t_-_s_t_r_i_n_g]

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

       [--YY|----aalltt--yy--ggrriidd]

       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).

       [--oo|----llooggaarriitthhmmiicc]

       Logarithmic y-axis scaling.

       [--XX|----uunniittss--eexxppoonneenntt _v_a_l_u_e]

       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 ----aalltt--yy--ggrriidd mode.

       [--LL|----uunniittss--lleennggtthh _v_a_l_u_e]

       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.

       [----uunniittss==ssii]

       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.

   RRiigghhtt YY AAxxiiss
       [----rriigghhtt--aaxxiiss _s_c_a_l_e::_s_h_i_f_t] [----rriigghhtt--aaxxiiss--llaabbeell _l_a_b_e_l]

       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.

       [----rriigghhtt--aaxxiiss--ffoorrmmaatttteerr _f_o_r_m_a_t_t_e_r_-_n_a_m_e]

       Specify what formatter to use to render axis values.

       nnuummeerriicc
           The default, values are expressed as numeric quantities.

       ttiimmeessttaammpp
           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 ----uunniittss--lleennggtthh and
           ----rriigghhtt--aaxxiiss--ffoorrmmaatt.

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

       [----rriigghhtt--aaxxiiss--ffoorrmmaatt _f_o_r_m_a_t_-_s_t_r_i_n_g]

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

   LLeeggeenndd
       [--gg|----nnoo--lleeggeenndd]

       Suppress generation of the legend; only render the graph.

       [--FF|----ffoorrccee--rruulleess--lleeggeenndd]

       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).

       [----lleeggeenndd--ppoossiittiioonn=(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.

       [----lleeggeenndd--ddiirreeccttiioonn=(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.

   MMiisscceellllaanneeoouuss
       [--zz|----llaazzyy]

       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.

       [--dd|----ddaaeemmoonn _a_d_d_r_e_s_s]

       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 --ll option in
       the rrdcached manual.

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

       [--ff|----iimmggiinnffoo _p_r_i_n_t_f_s_t_r]

       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
       _f_i_l_e_n_a_m_e, _x_s_i_z_e and _y_s_i_z_e. In order to generate an IIMMGG 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">'

       [--cc|----ccoolloorr _C_O_L_O_R_T_A_G#_r_r_g_g_b_b[_a_a]]

       Override the default colors for the standard elements of the graph. The
       _C_O_L_O_R_T_A_G 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"

       [----ggrriidd--ddaasshh _o_n::_o_f_f]

       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

       [----bboorrddeerr _w_i_d_t_h]

       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.

       [----ddyynnaammiicc--llaabbeellss]

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

       [--mm|----zzoooomm _f_a_c_t_o_r]

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

       [--nn|----ffoonntt _F_O_N_T_T_A_G::_s_i_z_e[::_f_o_n_t]]

       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 ----ffoonntt 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 "[_F_A_M_I_L_Y_-_L_I_S_T] [_S_T_Y_L_E_-_O_P_T_I_O_N_S] [_S_I_Z_E]",
       where _F_A_M_I_L_Y_-_L_I_S_T is a comma separated list of families optionally
       terminated by a comma, _S_T_Y_L_E___O_P_T_I_O_N_S is a whitespace separated list of
       words where each WORD describes one of style, variant, weight, stretch,
       or gravity, and _S_I_Z_E 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.

       [--RR|----ffoonntt--rreennddeerr--mmooddee {nnoorrmmaall,lliigghhtt,mmoonnoo}]

       There are 3 font render modes:

       nnoorrmmaall: Full Hinting and Anti-aliasing (default)

       lliigghhtt: Slight Hinting and Anti-aliasing

       mmoonnoo: Full Hinting and NO Anti-aliasing

       [--BB|----ffoonntt--ssmmooootthhiinngg--tthhrreesshhoolldd _s_i_z_e]

       (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.

       [--PP|----ppaannggoo--mmaarrkkuupp]

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

        <span key="value">text</span>

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

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

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

       [--GG|----ggrraapphh--rreennddeerr--mmooddee {nnoorrmmaall,mmoonnoo}]

       There are 2 render modes:

       nnoorrmmaall: Graphs are fully Anti-aliased (default)

       mmoonnoo: No Anti-aliasing

       [--EE|----ssllooppee--mmooddee]

       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.

       [--aa|----iimmggffoorrmmaatt PPNNGG|SSVVGG|EEPPSS|PPDDFF|XXMMLL|XXMMLLEENNUUMM|JJSSOONN|JJSSOONNTTIIMMEE|CCSSVV|TTSSVV|SSSSVV]

       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 (enummerates 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")

       [--ii|----iinntteerrllaacceedd]

       (this gets ignored in 1.3 for now!)

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

       [--TT|----ttaabbwwiiddtthh _v_a_l_u_e]

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

       [--bb|----bbaassee _v_a_l_u_e]

       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.

       [--WW|----wwaatteerrmmaarrkk _s_t_r_i_n_g]

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

       [--ZZ|----uussee--nnaann--ffoorr--aallll--mmiissssiinngg--ddaattaa]

       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.

   DDaattaa aanndd vvaarriiaabblleess
       DDEEFF::_v_n_a_m_e==_r_r_d_f_i_l_e::_d_s_-_n_a_m_e::_C_F[::sstteepp==_s_t_e_p][::ssttaarrtt==_t_i_m_e][::eenndd==_t_i_m_e]

       CCDDEEFF::_v_n_a_m_e==_R_P_N _e_x_p_r_e_s_s_i_o_n

       VVDDEEFF::_v_n_a_m_e==_R_P_N _e_x_p_r_e_s_s_i_o_n

       You need at least one DDEEFF and one LLIINNEE, AARREEAA, GGPPRRIINNTT, PPRRIINNTT statement
       to generate anything useful.

       See rrdgraph_data and rrdgraph_rpn for the exact format.

       NOTE: GGrraapphh aanndd pprriinntt eelleemmeennttss

       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.

   ggrraapphhvv
       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.

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

       RRRRDDCCAACCHHEEDD__AADDDDRREESSSS
           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.

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

SSEEEE AALLSSOO
       rrdgraph gives an overview of how rrrrddttooooll ggrraapphh works.  rrdgraph_data
       describes DDEEFF,CCDDEEFF and VVDDEEFF in detail.  rrdgraph_rpn describes the RRPPNN
       language used in the ??DDEEFF statements.  rrdgraph_graph page describes
       all of the graph and print functions.

       Make sure to read rrdgraph_examples for tips&tricks.

AAUUTTHHOORR
       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



1.5.999                           2016-05-23                       RRDGRAPH(1)
