Hi, At Cominvent we've often had the need to visualize the internal architecture of Apache Solr in order to explain both the relationships of the components as well as the flow of data and queries. The result is a conceptual architecture diagram, clearly showing how Solr relates to the app-server, how cores relate to a Solr instance, how documents enter through an UpdateRequestHandler, through an UpdateChain and Analysis and into the Lucene index etc.
The drawing is created using Google draw, and the original is shared on Google Docs. We have licensed the diagram under the permissive Creative Commons "CC-by" license which lets you use, modify and re-distribute the diagram, even commercially, as long as you attribute us with a link. Check it out at http://ow.ly/4sOTm We'd love your comments -- Jan Høydahl, search solution architect Cominvent AS - www.cominvent.com
