_R_R_D_C_G_I(1)                            rrdtool                           _R_R_D_C_G_I(1)

NNAAMMEE
     rrdcgi - Create web pages containing RRD graphs based on templates

SSYYNNOOPPSSIISS
     "#!/path/to/"rrrrddccggii [----ffiilltteerr|--ff]

DDEESSCCRRIIPPTTIIOONN
     rrrrddccggii  is a sort of very limited script interpreter. Its purpose is to run
     as a cgi-program and parse a web page template  containing  special  <RRD::
     tags. rrrrddccggii will interpret and act according to these tags.  In the end it
     will printout a web page including the necessary CGI headers.

     rrrrddccggii  parses  the  contents  of  the template in 3 steps. In each step it
     looks only for a subset of tags. This allows nesting of tags.

     The argument parser uses the same semantics  as  you  are  used  from  your
     C-shell.

     ----ffiilltteerr|--ff
             Assume that rrdcgi is run as a filter and not as a cgi.

   KKeeyywwoorrddss
     RRD::CV _n_a_m_e
             Inserts the CGI variable of the given name.

     RRD::CV::QUOTE _n_a_m_e
             Inserts the CGI variable of the given name but quotes it, ready for
             use  as  an  argument  in another RRD:: tag. So even when there are
             spaces in the value of the CGI variable it will still be considered
             to be one argument.

     RRD::CV::PATH _n_a_m_e
             Inserts the CGI variable of the given name,  quotes  it  and  makes
             sure  it  starts  neither  with a '/' nor contains '..'. This is to
             make sure that no problematic pathnames can be  introduced  through
             the CGI interface.

     RRD::GETENV _v_a_r_i_a_b_l_e
             Get the value of an environment variable.

              <RRD::GETENV REMOTE_USER>

             might give you the name of the remote user given you are using some
             sort of access control on the directory.

     RRD::GOODFOR _s_e_c_o_n_d_s
             Specify  the  number of seconds this page should remain valid. This
             will prompt the rrdcgi to output a Last-Modified, an Expire and  if
             the number of seconds is _n_e_g_a_t_i_v_e a Refresh header.

     RRD::INCLUDE _f_i_l_e_n_a_m_e
             Include  the  contents of the specified file into the page returned
             from the cgi.

     RRD::SETENV _v_a_r_i_a_b_l_e _v_a_l_u_e
             If you want to present your graphs in another time zone  than  your
             own, you could use

              <RRD::SETENV TZ UTC>

             to  make  sure everything is presented in Universal Time. Note that
             the values permitted to TZ depend on your OS.

     RRD::SETVAR _v_a_r_i_a_b_l_e _v_a_l_u_e
             Analog to SETENV but for local variables.

     RRD::GETVAR _v_a_r_i_a_b_l_e
             Analog to GETENV but for local variables.

     RRD::TIME::LAST _r_r_d_-_f_i_l_e _s_t_r_f_t_i_m_e_-_f_o_r_m_a_t
             This gets replaced by the last modification time  of  the  selected
             RRD.  The  time  is _s_t_r_f_t_i_m_e-formatted with the string specified in
             the second argument.

     RRD::TIME::NOW _s_t_r_f_t_i_m_e_-_f_o_r_m_a_t
             This gets replaced by the current time of day. The  time  is  _s_t_r_f_‐
             _t_i_m_e-formatted with the string specified in the argument.

             Note  that  if  you return : (colons) from your strftime format you
             may have to escape them using \ if the time is to be used as an ar‐
             gument to a GRAPH command.

     RRD::TIME::STRFTIME _S_T_A_R_T_|_E_N_D _s_t_a_r_t_-_s_p_e_c _e_n_d_-_s_p_e_c _s_t_r_f_t_i_m_e_-_f_o_r_m_a_t
             This gets replaced by a strftime-formatted time  using  the  format
             _s_t_r_f_t_i_m_e_-_f_o_r_m_a_t  on  either  _s_t_a_r_t_-_s_p_e_c  or  _e_n_d_-_s_p_e_c  depending on
             whether _S_T_A_R_T or _E_N_D is specified.  Both  _s_t_a_r_t_-_s_p_e_c  and  _e_n_d_-_s_p_e_c
             must be supplied as either could be relative to the other.  This is
             intended  to allow pretty titles on graphs with times that are eas‐
             ier for non RRDtool folks to figure out than "-2weeks".

             Note that again, if you return : (colon) from your strftime format,
             you may have to escape them using \ if the time is to be used as an
             argument to a GRAPH command.

     RRD::GRAPH _r_r_d_g_r_a_p_h _a_r_g_u_m_e_n_t_s
             This tag creates the RRD graph defined by its argument and then  is
             replaced  by  an appropriate <IMG ... > tag referring to the graph.
             The ----llaazzyy option in RRD graph can be used to make sure that graphs
             are only regenerated when they are out of date.  The  arguments  to
             the RRRRDD::::GGRRAAPPHH tag work as described in the rrrrddggrraapphh manual page.

             Use  the  ----llaazzyy option in your RRD::GRAPH tags, to reduce the load
             on your server. This option makes sure that graphs are only  regen‐
             erated when the old ones are out of date.

             If you do not specify your own ----iimmggiinnffoo format, the following will
             be used:

              <IMG SRC="%s" WIDTH="%lu" HEIGHT="%lu">

             Note  that  %s stands for the filename part of the graph generated,
             all directories given in the PNG file argument will get dropped.

     RRD::PRINT _n_u_m_b_e_r
             If the preceding  RRRRDD::::GGRRAAPPHH tag  contained  any  PPRRIINNTT  arguments,
             then you can access their output with this tag. The _n_u_m_b_e_r argument
             refers  to  the  number  of the PPRRIINNTT argument. The first PPRRIINNTT has
             _n_u_m_b_e_r 0.

     RRD::INTERNAL <var>
             This tag gets replaced by an internal var. Currently these vars are
             known: VERSION, COMPILETIME.  These vars represent the  compiled-in
             values.

EEXXAAMMPPLLEE 11
     The example below creates a web page with a single RRD graph.

      #!/usr/local/bin/rrdcgi
      <HTML>
      <HEAD><TITLE>RRDCGI Demo</TITLE></HEAD>
      <BODY>
      <H1>RRDCGI Example Page</H1>
      <P>
      <RRD::GRAPH demo.png --lazy --title="Temperatures"
               DEF:cel=demo.rrd:exhaust:AVERAGE
               LINE2:cel#00a000:"D. Celsius">

      </P>
      </BODY>
      </HTML>

EEXXAAMMPPLLEE 22
     This script is slightly more elaborate, it allows you to run it from a form
     which  sets RRD_NAME. RRD_NAME is then used to select which RRD you want to
     use as source for your graph.

      #!/usr/local/bin/rrdcgi
      <HTML>
      <HEAD><TITLE>RRDCGI Demo</TITLE></HEAD>
      <BODY>
      <H1>RRDCGI Example Page for <RRD::CV RRD_NAME></H1>
      <H2>Selection</H2>
      <FORM><INPUT NAME=RRD_NAME TYPE=RADIO VALUE=roomA> Room A,
            <INPUT NAME=RRD_NAME TYPE=RADIO VALUE=roomB> Room B.
            <INPUT TYPE=SUBMIT></FORM>
      <H2>Graph</H2>
      <P>
      <RRD::GRAPH <RRD::CV::PATH RRD_NAME>.png --lazy
               --title "Temperatures for "<RRD::CV::QUOTE RRD_NAME>
               DEF:cel=<RRD::CV::PATH RRD_NAME>.rrd:exhaust:AVERAGE
               LINE2:cel#00a000:"D. Celsius">

      </P>
      </BODY>
      </HTML>

EEXXAAMMPPLLEE 33
     This example shows how to  handle  the  case  where  the  RRD,  graphs  and
     cgi-bins are separate directories

      #!/.../bin/rrdcgi
      <HTML>
      <HEAD><TITLE>RRDCGI Demo</TITLE></HEAD>
      <BODY>
      <H1>RRDCGI test Page</H1>
      <RRD::GRAPH
       /.../web/pngs/testhvt.png
       --imginfo '<IMG SRC=/.../pngs/%s WIDTH=%lu HEIGHT=%lu >'
       --lazy --start -1d --end now
       DEF:http_src=/.../rrds/test.rrd:http_src:AVERAGE
       AREA:http_src#00ff00:http_src
      >
      </BODY>
      </HTML>

     Note 1: Replace /.../ with the relevant directories

     Note  2:  The  SRC=/.../pngs  should  be  paths  from  the view of the web‐
     server/browser

AAUUTTHHOORR
     Tobias Oetiker <tobi@oetiker.ch>

1.10.0                             2026-05-23                          _R_R_D_C_G_I(1)
