Installation

Cacti plugin and Editor

Requirements

Before doing anything else, please verify that your Plugin Architecture is working properly with a simpler plugin, like Links or Tools. Weathermap is relatively complex, and fault-finding both your Cacti Plugin Architecture and Weathermap at the same time will make life harder for you!

You will need the 'pcre' and 'gd' PHP modules in both your command-line and server-side (mod_php/ISAPI) PHP. The poller-process runs using the command-line PHP, and the editor uses the server-side one. In some situations it is possible to have two completely different PHP installations serving these two - if you install from a package, then re-install from source, but to a different directory, for example. The editor and the poller process should both warn you if the part they need is not present.

You can then use the pre-install checker to see if your PHP environment has everything it needs. To do this, you need to run a special check.php script, twice...

First, go to http://yourcactiserver/plugins/weathermap/check.php to see if your webserver PHP (mod_php, ISAPI etc) is OK. Then, from a command-prompt run php check.php to see if your command-line PHP is OK. If any modules or functions are missing, you will get a warning, and an explanation of what will be affected (not all of the things that are checked are deadly problems).

Before you start using it, you might want to change one PHP setting. Weathermap uses a fair bit of memory by PHP standards, as it builds the image for the map in memory before saving it. As a result, your PHP process may run out of memory. PHP has a 'safety valve' built-in, to stop runaway scripts from killing your server, which defaults to 8MB in most versions (this has changed in 5.2.x). This is controlled by the 'memory_limit =' line in php.ini. You may need to increase this to 32MB or even more if you have problems. In fact, the current Cacti manual suggests 128MB. These problems will typically show up as the poller process just dying with no warning or error message, as PHP kills the script.

Installation

To use the Cacti plugin, you must unpack the zip file into a directory called '<cacti_root>/plugins/weathermap'. The zip contains a folder called 'weathermap' already, so unzipping it in the plugins folder should do the job.

File Permissions

You will need to change the permissions on the output directory, so that the Cacti poller process can write to it. This is the same as you would have done for the rra directory while installing Cacti itself originally. For a *nix system, it will be something like:

                                chown cactiuser output

Getting Started

Log in to the Cacti application, and go to the Plugin Management page. You should see the Weathermap plugin as an uninstalled plugin. Click the 'install' icon next to its name, and then click the 'enable' icon that appears next to that. If you are logged in as the 'admin' user, you should see the 'Weathermap' tab appear at the top of the Cacti page.

That's it! The Weathermap plugin is installed.

To allow other users to see it, you need to go to the User Management page in Cacti, and grant those users the extra permissions that should appear there now, to either View Weathermaps (for customers) and/or Manage Weathermaps (for admin users).

To go further, you need some weathermap configuration files to define your maps. You can do this in two ways - using the Web-based map editor, or by editing the text-based configuration files directly.

To use the editor, you need to make a few more changes (see below).

To learn more about actually using the Cacti plugin, see the Cacti Plugin page.

The Editor

Once you have weathermap itself working, continue onto the editor:

Copy the editor-config.php-dist file to editor-config.php. If you want to be able to pick data sources from your Cacti installation by name, edit the file and make sure that the line that sets $cacti_base is correct, and that the base URI below that is also correct for your Cacti installation (these two lines are marked CHANGE in the file).

Make sure that your webserver can write to the configs directory. To do this, you need to know which user your webserver runs as (maybe 'nobody', 'www' or 'httpd' on most *nixes) and then run:

chown www configs
                                chmod u+w configs
In a pinch, you can just chmod 777 configs, but this really isn't a recommended solution for a production system.

On Windows, the same applies - the user that runs the webserver runs as should have permissions to write new files, and change existing files in the configs folder.

Since version 0.98, you no longer need to edit the editor.php to enable it unless you want to use the editor outside of Cacti. Otherwise, you can edit existing maps by clicking on their name in the list of maps in the Cacti Manage..Weathermaps page, or by clicking the 'Weathermap Editor' link at the bottom of the page to create new maps or edit maps not currently being used.

You will need to have the Cacti permission 'Edit Weathermaps' to be able to do this.

Please see the editor manual page for more about using the editor! And check the 'CLI Editor installation' page for information about using the editor without Cacti integration.

You can also edit an existing map from the Cacti web interface, by choosing Manage..Weathermaps and then clicking on the name of a config file in the list of active maps. The editor will open with that map loaded.

Important Security Note: The editor allows anyone who can access editor.php to change the configuration files for your network weathermaps. There is no authentication built-in for editing, except with the Cacti Plugin. This is why direct access to the editor is disabled by default - the editor won't work until you choose to make it work, or give permissions in Cacti. It's recommended that you either:

  • change the ownership of configuration files so that the editor can't write to them once they are complete, or
  • use your webserver's authentication and access control facilities to limit who can access the editor.php URL. On apache, this can be done using the FilesMatch directive and mod_access.