Installing the RAT module
To install the Raster Attribute Table support:
From the website download page, locate your release, and download: http://sourceforge.net/projects/geoserver/files/GeoServer/2.26.1/extensions/geoserver-2.26.1-rat-plugin.zip
Warning
Make sure to match the version of the extension to the version of GeoServer.
Extract these files and place the JARs in
WEB-INF/lib
.Perform any configuration required by your servlet container, and then restart.