The target for this request is the Geoportal Server Team. With the release of Geoportal Server version 1.2.4 one of the items described as "What's New" was an "initial sample integration of Apache SOLR to enable faceting a catalog and distributing an index." When our Bureau stood up the new version of Geoportal 1.2.4, we also stood up an instance of Geoportal Facets customization (GFC). Our instance of GFC through testing proved promising but it's still sitting there and has not been developed or integrated with our working solution.
Recent ESRI presentations have indicated increased support for this is "Farther Down the Road" and I would like to see ESRI provide more support for this product which leverages the Apache SOLR index taking it beyond a sample customization to a more full blown integration option for Geoportal Server. When tested GFC seemed to provide a much faster Search and Discovery for an improved user experience.
The architecture can be found on the Geoportal Facets page in GitHub (https://github.com/Esri/geoportal-server/wiki/Geoportal-Facets) and is described as: "You can see that solr is deployed separately from the Esri Geoportal Server, and maintains a separate lucene index. Records can be pushed into this index from the Esri Geoportal Server or from other systems. The Custom solr UI exposes the solr index; this UI can be placed into the Esri Geoportal Server page structure, or can be maintained outside of the Esri Geoportal Server." It would be really helpful if ESRI could build upon the best practice for deployment of the custom SOLR user interface, or integration with Geoportal Server page structure, so this could be leveraged toward a more out-of-the-box functionality, with less emphasis on the need for a developer's role or networking with other users who have taken a deeper dive in implementing this promising component.