Today Pantheon announces a removal schedule for Solr 3 on February 9, 2027 and Solr 8 on July 11, 2027. Solr 9 will reach General Availability on June 30, 2026 ahead of these removals.
After a Solr version is removed from the platform, sites using that version will no longer be able to index content or return search results. Views, blocks, or other components that rely on Solr-powered search indexes may return no results or throw errors.
Solr 9 - General Availability: June 30, 2026
Solr 9 has been available as a Beta for Drupal 10 and 11 sites through search_api_pantheon version 8.5.0-beta1. Solr 9 Beta for Drupal 7 is now available as of May 12, 2026.
General Availability for Solr 9 is targeted for June 30, 2026.
Solr 3 - Removal: February 9, 2027
Solr 3 will be removed from the Pantheon platform on February 9, 2027. Solr 3 is a legacy search version that no longer receives security updates.
Previous milestones:
Drupal 7 sites still using Solr 3 must migrate to Solr 9 before this date. See the Solr for Drupal 7 guide for upgrade steps. WordPress sites should migrate to Elasticsearch or another supported search solution before January 11, 2027.
Solr 8 - Removal: July 11, 2027
Solr 8 (8.11.4) will be removed from the platform on July 11, 2027. Solr 9 supersedes Solr 8 with improved security defaults and other enhancements. Drupal 10 and 11 sites currently running Solr 8 should migrate to Solr 9 before this date. Upgrade instructions are available in the Solr 9 Beta announcement.
Action required
-
Drupal:
- Solr 3 sites: Migrate to Solr 9 before February 9, 2027.
- Solr 8 sites: Migrate to Solr 9 before July 11, 2027.
For guidance on upgrading, see Drupal Solr.
-
WordPress:
- Migrate to Elasticsearch before January 11, 2027.