# CactiView v0.2 - Laurie Denness
#       Displays a section of Cacti graphs based on your selection.
#       Graphs rotate automatically every 20 seconds (by default)
#       Configuration is available in config.php
#
#       http://laurie.denness.net - laurie@denness.net
#


DISCLAIMER: I am not a PHP developer. I am a sysadmin. This code is probably not 100% glamorous, 
but it works. If you have any problems, I'm sure they won't be hard to solve; and I cannot be
held responsible if you lose data, time, your girlfriend, your house, or anything else from 
using this code. 


0. Requirements

- PHP
- Cacti or Ganglia
- A monitor dedicated for graphs, preferably hanging from the ceiling or wall. 
- A web browser running on a computer attached to said monitor

1. Limitations

At the present time, this is intended for a specific screen resolution and there is no easy
way to change this dynamically. If it doesn't quite fit, please manually alter the size of the
graphs using the numbers in graphview.php. 

2. What it does 

CactiView gives you a clean and simple view of one data source from Cacti at a time, or a host
or cluster from Ganglia. You can name the data sources, and set the automatic rotation duration. 

You can see how this looks here: http://www.flickr.com/photos/lozzd/3210562508/

One main large graph for the last 12 hours, 3 smaller graphs with longer time periods and a 
couple of other bits and bobs of information. (Ganglia displays the last hour of load, memory,
network and CPU)

3. Configuration

To get the most of CactiView, you should make a couple of simple changes to your Cacti
installation. These are optional, but will improve the output of CactiView. More details later.
The same applies to Ganglia. 

The actual configuration of CactiView is very simple. You do not even have to run CactiView on
the same server as Cacti. Each configuration option is detailed in the config file, config.php. 
At the very least, you should set a sensible timeout, the web path to Cacti (to display the 
actual graphs) and of course the graphs. All that is required for this is the internal ID of
the graph in Cacti, and a name for the graph. 

4. Using CactiView

After configuration, open a browser (I suggest Google Chrome, more here:
http://laurie.denness.net/blog/2009/05/finding-a-web-browser-for-constant-page-reloading/ )
and point it to where you installed CactiView. e.g. http://host/cactiview

You should land at your first graph, and after the timeout, it will rotate to the next graph
in the array until it hits the last at which point it will start again at the being. This repeats
forever. 

5. Hints and tips

If displaying this unattended constantly, it is a good idea to use a method to turn off the 
display when no one will be looking at it (if possible!). On Windows, I provide a couple of
small .exe files, one which sleeps the displays, and one to wake them. You can then use 
Task Scheduler to have the monitors be controlled automatically. Using Linux, you can use
dpms to sleep and wake the monitors using cron. 

6. Modifying Cacti

To remove the graph title from the CactiView graphs to make the display cleaner, you need 
to add a small amount of code to Cacti itself. This is optional, but recommended. 

--- cacti-0.8.7d/lib/rrd.php       2009-02-12 02:55:50.000000000 +0000
+++ cacti/lib/rrd.php   2009-04-01 16:41:08.961126012 +0000
@@ -830,6 +830,16 @@
                }
        }

+        /* Last.fm modification, allow us to get a basic graph for CactiView */
+
+    if (isset($_GET['notitle'])) {
+        $graph["title_cache"] = '';
+        $graph["vertical_label"] = '';
+        $graph_opts .= "-c MGRID#888888" . RRD_NL;
+        $graph_opts .= "--slope-mode" . RRD_NL;
+    }
+
+

7. Modifying Ganglia

To allow for custom sizes posted into the URL of the graph.php graph creation script
in Ganglia, you need to add the following: (put the lines anywhere as long as Ganglia does
not overwrite the width variable again! Near the bottom is best.)

--- ./ganglia_backup/graph.php  2009-06-25 10:03:13.000000000 +0000
+++ ./ganglia/graph.php 2010-03-28 17:38:52.013814265 +0000
@@ -179,6 +176,14 @@
     $rrdtool_graph['title'] = "$title " . $rrdtool_graph['title'];
 }

+if (isset($_GET['width'])) {
+   $rrdtool_graph['width'] = $_GET['width'];
+}
+
+if (isset($_GET['height'])) {
+   $rrdtool_graph['height'] = $_GET['height'];
+}
+


8. Help me!

No! Well maybe. Send me an email, and I can probably offer some advice. I apologise if not!