.. _identify:

Make cluster nodes identifiable from the GUI
============================================

When running one or more clusters of GeoServer installations it is useful to identify which 
cluster (and eventually which node of the cluster) one is working against by just glancing
the web administration UI.

This is possible by setting one variable, ``GEOSERVER_NODE_OPTS``, with one of the supported
mechanisms:

  * as a system variable
  * as an environment variable
  * as a servlet context parameter

``GEOSERVER_NODE_OPTS`` is a semicolumn separate list of key/value pairs and it can contain the following keys:

  * id: the string identifying the node, which in turn can be a static string, or use the ``$host_ip`` and ``$host_name`` to report the host IP address or host name respectively
  * color: the label color, as a CSS color
  * background: the background color, as a CSS color

Here are some examples:

.. figure:: images/custom_id.png
   :align: center

   *GEOSERVER_NODE_OPTS="id:test1;background:black;color:white"*

   
.. figure:: images/host_ip.png
   :align: center

   *GEOSERVER_NODE_OPTS="id:$host_ip"*

.. figure:: images/host_name.png
   :align: center

   *GEOSERVER_NODE_OPTS="id:$host_name"*