


RRDGRAPH(1)                  RRDtool                  RRDGRAPH(1)


NAME
       rrdgraph - Create a graph based on data from one or sev-
       eral RRD

SYNOPSIS
       rrdtool graph filename [-s|--start seconds] [-e|--end sec-
       onds] [-x|--x-grid x-axis grid and label]
       [-y|--y-grid y-axis grid and label] [-Y|--alt-y-grid]
       [-R|--alt-y-mrtg] [-A|--alt-autoscale]
       [-M|--alt-autoscale-max] [-N|--no-minor] [-X|--units-expo-
       nent] value]> [-L|--units-length] value]>
       [-v|--vertical-label text] [-w|--width pixels]
       [-h|--height pixels] [-i|--interlaced] [-f|--imginfo for-
       matstring] [-a|--imgformat GIF|PNG|GD]
       [-B|--background value] [-O|--overlay value]
       [-U|--unit value] [-z|--lazy] [-o|--logarithmic]
       [-u|--upper-limit value] [-l|--lower-limit value]
       [-g|--no-legend] [-j|--only-graph] [-F|--force-rules-leg-
       end] [-r|--rigid] [-S|--step value] [-b|--base value]
       [-c|--color COLORTAG#rrggbb] [-t|--title title]
       [DEF:vname=rrd:ds-name:CF] [CDEF:vname=rpn-expression]
       [PRINT:vname:CF:format] [GPRINT:vname:CF:format] [COM-
       MENT:text] [HRULE:value#rrggbb[:legend]]
       [VRULE:time#rrggbb[:legend]]
       [LINE{1|2|3}:vname[#rrggbb[:legend]]]
       [AREA:vname[#rrggbb[:legend]]] [STACK:vname[#rrggbb[:leg-
       end]]]

DESCRIPTION
       The graph functions main purpose is to create graphical
       representations of the data stored in one or several RRDs.
       Apart from generating graphs, it can also extract numeri-
       cal reports.

       filename
           The name of the graph to generate. Since RRDTool out-
           puts GIFs and PNGs, it's recommended that the filename
           end in either .gif or .png.  RRDTool does not enforce
           this, however.  If the  filename is set to '-' the
           image file will be written to standard out.  All other
           output will get suppressed.

           PNG output is recommended, since it takes up to 40%
           less disk space and 20-30% less time to generate than
           a GIF file.

           If no graph functions are called, the graph will not
           be created.

       -s|--start seconds (default end-1day)
           The time when the graph should begin. Time in seconds
           since epoch (1970-01-01) is required. Negative numbers
           are relative to the current time. By default one day
           worth of data will be graphed.  See also AT-STYLE TIME



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           SPECIFICATION section in the rrdfetch documentation
           for a detailed explanation on how to specify time.

       -e|--end seconds (default now)
           The time when the graph should end. Time in seconds
           since epoch.  See also AT-STYLE TIME SPECIFICATION
           section in the rrdfetch documentation for a detailed
           explanation of ways to specify time.

       -x|--x-grid x-axis grid and label (default autoconfigure)
           The x-axis label is quite complex to configure. So if
           you don't have very special needs, you can rely on the
           autoconfiguration to get this right.

           If you want no x-grid at all, use the magic setting
           none.

           The x-axis label and grid can be configured, using the
           following format:

           GTM:GST:MTM:MST:LTM:LST:LPR:LFM

           You have to configure three elements making up the
           x-axis labels and grid. The base grid (G??), the major
           grid (M??) and the labels (L??). The configuration is
           based on the idea that you first specify a well known
           amount of time (?TM) and then say how many times it
           has to pass between each grid line or label (?ST). For
           the label you have to define two additional items: The
           precision of the label in seconds (LPR) and the strf-
           time format used to generate the text of the label
           (LFM).

           The ?TM elements must be one of the following key-
           words: SECOND, MINUTE, HOUR, DAY, WEEK, MONTH or YEAR.

           If you wanted a graph with a base grid every 10 min-
           utes and a major one every hour, with labels every
           hour you would use the following x-axis definition.

           "MINUTE:10:HOUR:1:HOUR:1:0:%X"

           The precision in this example is 0 because the %X for-
           mat is exact. If the label was the name of the day, we
           would have had a precision of 24 hours, because when
           you say something like 'Monday' you mean the whole day
           and not Monday morning 00:00. Thus the label should be
           positioned at noon. By defining a precision of 24
           hours or rather 86400 seconds, you make sure that this
           happens.

           If you want to alter the generated text to another
           language, use the LC_TIME environment variable to set
           the locale you prefer prior to calling the graph



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           function.

       -y|--y-grid grid step:label factor (default autoconfigure)
           Makes vertical grid lines appear at grid step inter-
           val. Every label factor gridstep, a major grid line is
           printed, along with label showing the value of the
           grid line.

           If you want no y-grid at all set specify the magic
           word none.

       -Y|--alt-y-grid
           Place Y grid dynamically based on graph Y range. Algo-
           rithm ensures that you always have grid, that there
           are enough but not too many grid lines and the grid is
           metric. That is grid lines are placed every 1, 2, 5 or
           10 units.  (contributed by Sasha Mikheev)

       --no-minor
           Turn off the minor grid lines.  This is particularly
           useful for small graphs which can be cluttered with
           the minor grid lines. (contributed by Travis Brown)

       -R|--alt-y-mrtg
           Y grid placed on graph Y range mimics MRTG's
           (rateup-generated) graphs.  Currently axis is split
           into 4 parts, just as rateup does.

       -A|--alt-autoscale
           Compute Y range  based on function absolute minimum
           and maximum values. Default algorithm uses predefined
           set of ranges.  This is good in many cases but it
           fails miserably when you need to graph something like
           260 + 0.001 * sin(x). Default algorithm will use Y
           range from 250 to 300 and on the graph you will see
           almost straight line. With --alt-autoscale Y range
           will be from slightly less the 260 - 0.001 to slightly
           more then 260 + 0.001 and periodic behavior will be
           seen.   (contributed by Sasha Mikheev)

       -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.

       -X|--units-exponent value (default autoconfigure)
           This sets the 10**exponent scaling of the y-axis val-
           ues.  Normally values will be scaled to the appropri-
           ate units (k, M, etc.).  However you may wish to dis-
           play units always in k (Kilo, 10e3) even if the data



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           is in the M (Mega, 10e6) range for instance.  Value
           should be an integer which is a multiple of 3 between
           -18 and 18 inclusive.  It is the exponent on the units
           you which 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, mil-
           lionths).  Use a value of 0 to prevent any scaling of
           the y-axis values.

       -L|--units-length value (default 9 characters)
           This sets the character width on the left side of the
           graph for y-axis values.

       -v|--vertical-label text
           vertical label on the left side of the graph. This is
           normally used to specify the units used.

       -w|--width pixels (default 400 pixel)
           Width of the drawing area within the graph. This
           affects the size of the gif.

       -h|--height pixels (default 100 pixel)
           Height of the drawing area within the graph. This
           affects the size of the gif.

       -i|--interlaced (default: false)
           If you set this option, then the resulting GIF will be
           interlaced.  Most web browsers display these incremen-
           tally as they load. If you do not use this option, the
           GIFs default to being progressive scanned. The only
           effect of this option is to control the format of the
           GIF on disk. It makes no changes to the layout or con-
           tents of the graph.

       -f|--imginfo formatstring
           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 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">'

       -a|--imgformat GIF|PNG|GD (default: GIF)
           Allows you to produce PNG or GD output from RRDTool.

       -B|--background value
           You could use image in (currently only) GD format for
           background. It is used as background at the very
           beginning of graph creation.





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       -O|--overlay value
           You could use image in (currently only) GD format as
           overlay. It is placed over created graph so that white
           pixel (color 255,255,255) is considered transparent,
           all other is replacing corresponding pixel in created
           graph.

       -U|--unit value
           You could use unit to be displayed on y axis. It is
           wise to use only short units on graph, however.

       -z|--lazy (default: false)
           Only generate the graph, if the current gif is out of
           date or not existent.

       -u|--upper-limit value (default autoconfigure)
           Defines the value normally located at the upper border
           of the graph. If the graph contains higher values, the
           upper border will move upwards to accommodate these
           values as well.

           If you want to define an upper-limit which will not
           move in any event you have to set the --rigid option
           as well.

       -l|--lower-limit value (default autoconfigure)
           This is not the lower limit of a graph.  But rather,
           this is the maximum lower bound of a graph.  For exam-
           ple, the value -100 will result in a graph that has a
           lower limit of -100 or less.  Use this keyword to
           expand graphs down.

       -r|--rigid
           rigid boundaries mode.  Normally rrdgraph will auto-
           matically expand the lower and upper limit if the
           graph contains a value outside the valid range. With
           the r option you can disable this behavior

       -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.

       -o|--logarithmic
           logarithmic y-axis scaling

       -c|--color COLORTAG#rrggbb (default colors)
           override the colors for the standard elements of the
           graph. The COLORTAG must be one of the following sym-
           bolic names: BACK ground, CANVAS, SHADEA left/top bor-
           der, SHADEB right/bottom border, GRID, MGRID major
           grid, FONT, FRAME and axis of the graph or ARROW. This
           option can be called multiple times to set several



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           colors.

       -g|--no-legend
           Suppress generation of legend; only render the graph.

       -j|--only-graph
           Suppress anything but the graph, works only for height
           < 64.

       -F|--force-rules-legend
           Force the generation of HRULE and VRULE legend even if
           those HRULE or VRULE will not be drawn because out of
           graph boundaries (mimics behaviour of pre 1.0.42 ver-
           sions).

       -t|--title text (default no title)
           Define a title to be written into the graph

       -S|--step value (default automatic)
           By default rrdgraph calculates the width of one pixel
           in the time domain and tries to get data at that reso-
           lution from the RRD. With this switch you can override
           this behavior. If you want rrdgraph to get data at 1
           hour resolution from the RRD, then you can set the
           step to 3600 seconds. Note, that a step smaller than 1
           pixel will be silently ignored.

       DEF:vname=rrd:ds-name:CF
           Define virtual name for a data source. This name can
           then be used in the functions explained below. The DEF
           call automatically chooses an RRA which contains CF
           consolidated data in a resolution appropriate for the
           size of the graph to be drawn.  Ideally this means
           that one data point from the RRA should be represented
           by one pixel in the graph.  If the resolution of the
           RRA is higher than the resolution of the graph, the
           data in the RRA will be further consolidated according
           to the consolidation function (CF) chosen.

       CDEF:vname=rpn-expression
           Create a new virtual data source by evaluating a math-
           ematical expression, specified in Reverse Polish Nota-
           tion (RPN). If you have ever used a traditional HP
           calculator you already know RPN. The idea behind RPN
           notation is, that you have a stack and push your data
           onto this stack. When ever you execute an operation,
           it takes as many data values from the stack as needed.
           The pushing of data is implicit, so when ever you
           specify a number or a variable, it gets pushed auto-
           matically.

           If this is all a big load of incomprehensible words
           for you, maybe an example helps (a more complete
           explanation is given in [1]): The expression vname+3/2



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           becomes "vname,3,2,/,+" in RPN. First the three values
           get pushed onto the stack (which now contains (the
           current value of) vname, a 3 and a 2).  Then the /
           operator pops two values from the stack (3 and 2),
           divides the first argument by the second (3/2) and
           pushes the result (1.5) back onto the stack. Then the
           + operator pops two values (vname and 1.5) from the
           stack; both values are added up and the result gets
           pushes back onto the stack. In the end there is only
           one value left on the stack: The result of the expres-
           sion.

           The rpn-expression in the CDEF function takes both,
           constant values as well as vname variables. The fol-
           lowing operators can be used on these values:

           +, -, *, /, %
               pops two values from the stack applies the
               selected operator and pushes the result back onto
               the stack. The % operator stands for the modulo
               operation.

           SIN, COS, LOG, EXP, FLOOR, CEIL
               pops one value from the stack, applies the
               selected function and pushes the result back onto
               the stack.

           LT, LE, GT, GE, EQ
               pops two values from the stack, compares them
               according to the selected condition and pushes
               either 1 back onto the stack if the condition is
               true and 0 if the condition was not true.

           IF  pops three values from the stack. If the last
               value is not 0, the second value will be pushed
               back onto the stack, otherwise the first value is
               pushed back.

               If the stack contains the values A, B, C, D, E are
               presently on the stack, the IF operator will pop
               the values E D and C of the stack. It will look at
               C and if it is not 0 it will push D back onto the
               stack, otherwise E will be sent back to the stack.

           MIN, MAX
               selects the lesser or larger of the two top stack
               values respectively

           LIMIT
               replaces the value with *UNKNOWN* if it is outside
               the limits specified by the two values above it on
               the stack.

                CDEF:a=alpha,0,100,LIMIT



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           DUP, EXC, POP
               These manipulate the stack directly.  DUP will
               duplicate the top of the stack, pushing the result
               back onto the stack.  EXC will exchange the top
               two elements of the stack, and POP will pop off
               the top element of the stack.  Having insufficient
               elements on the stack for these operations is an
               error.

           UN  Pops one value off the stack, if it is *UNKNOWN*,
               1 will be pushed back otherwise 0.

           UNKN
               Push an *UNKNOWN* value onto the stack.

           PREV
               Push *UNKNOWN* if its at the first value of a data
               set or otherwise the value of this CDEF at the
               previous time step. This allows you to perform
               calculations across the data.

           PREV(vname)
               Push *UNKNOWN* if its at the first value of the
               data set named vname or otherwise the value of the
               CDEF named vname at the previous time step.  This
               allows you to perform complex calculations across
               the data.

           INF, NEGINF
               Push a positive or negative infinite (oo) value
               onto the stack. When drawing an infinite number it
               appears right at the top or bottom edge of the
               graph, depending whether you have a positive or
               negative infinite number.

           NOW Push the current (real world) time onto the stack.

           TIME
               Push the time the current sample was taken onto
               the stack. This is the number of non-skip seconds
               since 0:00:00 January 1, 1970.

           LTIME
               This is like TIME + current timezone offset in
               seconds. The current offset takes daylight saving
               time into account, given your OS supports this. If
               you were looking at a sample, in Zurich, in sum-
               mer, the offset would be 2*3600 seconds, as Zurich
               at that time of year is 2 hours ahead of UTC.

               Note that the timezone offset is always calculated
               for the time the current sample was taken at. It
               has nothing to do with the time you are doing the
               calculation.



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           Please note that you may only use vname variables that
           you previously defined by either DEF or CDEF. Further-
           more, as of this writing (version 0.99.25), you must
           use at least one vname per expression, that is
           "CDEF:fourtytwo=2,40,+" will yield an error message
           but not a vname fourtytwo that's always equal to 42.

       PRINT:vname:CF:format
           Calculate the chosen consolidation function CF over
           the data-source variable vname and "printf" the result
           to stdout using format.  In the format string there
           should be a '%lf', '%lg' or '%le' marker in the place
           where the number should be printed.

           If an additional '%s' is found AFTER the marker, the
           value will be scaled and an appropriate SI magnitude
           unit will be printed in place of the '%s' marker. The
           scaling will take the '--base' argument into consider-
           ation!

           If a '%S' is used instead of a '%s', then instead of
           calculating the appropriate SI magnitude unit for this
           value, the previously calculated SI magnitude unit
           will be used.  This is useful if you want all the val-
           ues in a PRINT statement to have the same SI magnitude
           unit.  If there was no previous SI magnitude calcula-
           tion made, then '%S' behaves like a '%s', unless the
           value is 0, in which case it does not remember a SI
           magnitude unit and a SI magnitude unit will only be
           calculated when the next '%s' is seen or the next '%S'
           for a non-zero value.

           If you want to put a '%' into your PRINT string, use
           '%%' instead.

       GPRINT:vname:CF:format
           Same as PRINT but the result is printed into the graph
           below the legend.

       Caveat: When using the PRINT and GRPRINT functions to cal-
       culate data summaries over time periods bounded by the
       current time, it is important to note that the last sample
       will almost always yield a value of UNKNOWN as it lies
       after the last update time.  This can result in slight
       data skewing, particularly with the AVERAGE function.  In
       order to avoid this, make sure that your end time is at
       least one heartbeat prior to the current time.

       COMMENT:text
           Like GPRINT but the text is simply printed into the
           graph.

       HRULE:value#rrggbb[:legend]
           Draw a horizontal rule into the graph and optionally



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           add a legend

       VRULE:time#rrggbb[:legend]
           Draw a vertical rule into the graph and optionally add
           a legend

       LINE{1|2|3}:vname[#rrggbb[:legend]]
           Plot for the requested data, using the color speci-
           fied. Write a legend into the graph. The 3 possible
           keywords LINE1, LINE2, and LINE3 generate increasingly
           wide lines. If no color is defined, the drawing is
           done 'blind' this is useful in connection with the
           STACK function when you want to ADD the values of two
           data-sources without showing it in the graph.

       AREA:vname[#rrggbb[:legend]]
           Does the same as LINE?, but the area between 0 and the
           graph will be filled with the color specified.

       STACK:vname[#rrggbb[:legend]]
           Does the same as LINE?, but the graph gets stacked on
           top of the previous LINE?, AREA or STACK graph.
           Depending on the type of the previous graph, the STACK
           will be either a LINE? or an AREA.  This obviously
           implies that the first STACK must be preceded by an
           AREA or LINE? -- you need something to stack something
           onto in the first place ;)

           Note, that when you STACK onto *UNKNOWN* data, RRDTool
           will not draw any graphics ... *UNKNOWN* is not zero
           ... if you want it to zero then you might want to use
           a CDEF argument with IF and UN functions to turn
           *UNKNOWN* into zero ...

NOTES on legend arguments
       Escaping the colon

       In a ':' in a legend argument will mark the end of the
       legend. To enter a ':' into a legend, the colon must be
       escaped with a backslash '\:'.  Beware, that many environ-
       ments look for backslashes themselves, so it may be neces-
       sary to write two backslashes so that one is passed onto
       rrdgraph.

       String Formatting

       The text printed below the actual graph can be formated by
       appending special escaped characters at the end of a text.
       When ever such a character occurs, all pending text is
       pushed onto the graph according to the character speci-
       fied.

       Valid markers are: \j for justified, \l for left aligned,
       \r for right aligned and \c for centered. In the next



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       section there is an example showing how to use centered
       formating.

       Normally there are two space characters inserted between
       every two items printed into the graph. The space follow-
       ing a string can be suppressed by putting a \g at the end
       of the string. The \g also squashes any space inside the
       string if it is at the very end of the string. This can be
       used in connection with %s to suppress empty unit strings.

        GPRINT:a:MAX:%lf%s\g

       A special case is COMMENT:\s this inserts some additional
       vertical space before placing the next row of legends.

       When text has to be formated without special instructions
       from your side, RRDTool will automatically justify the
       text as soon as one string goes over the right edge. If
       you want to prevent the justification without forcing a
       newline, you can use the special tag \J at the end of the
       string to disable the auto justification.

NOTE on Return Values
       Whenever rrdgraph gets called, it prints a line telling
       the size of the gif it has just created to STDOUT. This
       line looks like this: XSIZExYSIZE.

EXAMPLE 1
         rrdtool graph demo.gif --title="Demo Graph" \
                 DEF:cel=demo.rrd:exhaust:AVERAGE \
                 "CDEF:far=cel,1.8,*,32,+"" \
                 LINE2:cel#00a000:"D. Celsius" \
                 LINE2:far#ff0000:"D. Fahrenheit\c"

EXAMPLE 2
       This example demonstrates the syntax for using IF and UN
       to set *UNKNOWN* values to 0.  This technique is useful if
       you are aggregating interface data where the start dates
       of the data sets doesn't match.

         rrdtool graph demo.gif --title="Demo Graph" \
                DEF:idat1=interface1.rrd:ds0:AVERAGE \
                DEF:idat2=interface2.rrd:ds0:AVERAGE \
                DEF:odat1=interface1.rrd:ds1:AVERAGE \
                DEF:odat2=interface2.rrd:ds1:AVERAGE \
                CDEF:agginput=idat1,UN,0,idat1,IF,idat2,UN,0,idat2,IF,+,8,* \
                CDEF:aggoutput=odat1,UN,0,odat1,IF,odat2,UN,0,odat2,IF,+,8,* \
                AREA:agginput#00cc00:Input Aggregate \
                LINE1:aggoutput#0000FF:Output Aggregate

       Assuming that idat1 has a data value of *UNKNOWN*, the
       CDEF expression

        idat1,UN,0,idat1,IF



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       leaves us with a stack with contents of 1,0,NaN and the IF
       function will pop off the 3 values and replace them with
       0.  If idat1 had a real value like 7942099, then the stack
       would have 0,0,7942099 and the real value would be the
       replacement.

EXAMPLE 3
       This example shows two ways to use the INF function. First
       it makes the background change color during half of the
       hours. Then, it uses AREA and STACK to draw a picture. If
       one of the inputs was UNKNOWN, all inputs are overlaid
       with another AREA.

         rrdtool graph example.png --title="INF demo" \
                DEF:val1=some.rrd:ds0:AVERAGE \
                DEF:val2=some.rrd:ds1:AVERAGE \
                DEF:val3=some.rrd:ds2:AVERAGE \
                DEF:val4=other.rrd:ds0:AVERAGE \
                CDEF:background=val4,POP,TIME,7200,%,3600,LE,INF,UNKN,IF \
                CDEF:wipeout=val1,val2,val3,val4,+,+,+,UN,INF,UNKN,IF \
                AREA:background#F0F0F0 \
                AREA:val1#0000FF:Value1 \
                STACK:val2#00C000:Value2 \
                STACK:val3#FFFF00:Value3 \
                STACK:val4#FFC000:Value4 \
                AREA:wipeout#FF0000:Unknown

       The first CDEF uses val4 as a dummy value. It's value is
       removed immediately from the stack. Then a decision is
       made based on the time that a sample was taken. If it is
       an even hour (UTC time !) then the area will be filled. If
       it is not, the value is set to UNKN and is not plotted.

       The second CDEF looks if any of val1,val2,val3,val4 is
       unknown. It does so by checking the outcome of
       sum(val1,val2,val3,val4). Again, INF is returned when the
       condition is true, UNKN is used to not plot the data.

       The different items are plotted in a particular order.
       First do the background, then use a normal area to overlay
       it with data. Stack the other data until they are all
       plotted. Last but not least, overlay everything with eye-
       hurting red to signal any unknown data.

       Note that this example assumes that your data is in the
       positive half of the y-axis otherwise you would have to
       add NEGINF in order to extend the coverage of the rea to
       whole graph.

AUTHOR
       Tobias Oetiker <oetiker@ee.ethz.ch>

REFERENCES
       [1] http://www.dotpoint.com/xnumber/rpn_or_adl.htm



1.0.49                      2004-04-06                         12


