Following is a list of requirements for the Clowder software. Besides JAVA you can have all other services/software installed on other machines and can configure clowder to communicate with these services.

SoftwareVersionRequired forNotes
JAVA1.8+alwaysThe clowder software is written in Scala and javascript and requires JAVA to execute. Clowder has been tested with OpenJDK
MongoDB3.2-3.5 (3.6 not supported)alwaysClowder uses MongoDB to store the information about the files and if configured the files as well.
RabbitMQ3.5+extractorsRabbitMQ is used to communicate between Clowder and the extractors. When deploying extractors it is required to deploy RabbitMQ as well.
ElasticSearch2.x+ (5.x not yet tested)searching

ElasticSearch is used to search Clowder. We have not tested clowder with version 2.0 or larger of ElasticSearch

GeoServer2.7+geospatial overlaysGeoServer is used to with the geospatial extractor to generate overlays for maps.