Aten Explains Proxy Model for Cross-Site Drupal Search on Pantheon

Managing search across related Drupal sites on Pantheon is the focus of a technical article published by Aten Design Group on 18 June 2026. Joel Steidl, vice president of engineering at Aten, explains a hub-and-spoke proxy model that lets one Drupal site own the Solr core while client sites route Search API Solr traffic through the hub. The article presents the pattern as a response to multi-site search requirements rather than as a general replacement for managed search services.

The article is significant for teams running multi-site Drupal architectures because Pantheon Search documentation says each environment has its own Solr server and indexed data. Aten’s approach works within that model by keeping direct Solr access on the hub site, exposing selected Solr actions through authenticated HTTP, and sending client requests through the proxy. This keeps the search index shared while leaving schema management and Pantheon Solr connectivity under the hub site.

The setup uses search_api_pantheon and pantheon_solr_api on the hub, with search_api_solr_proxy and search_api_solr_proxy_pantheon_connector on client sites. Aten describes API-key authentication through the Key module, a standalone pantheon-solr-proxy.php path for SELECT queries, hub-side schema management, and document namespacing by site hash and index ID. Drupal.org lists pantheon_solr_api and search_api_solr_proxy as projects not covered by Drupal’s security advisory policy, so implementation should be evaluated with that limitation in mind.