The search engine was updated from Solr 8.11.2 to Solr 9.2.1. Alongside, a new coremedia/solr-base Docker image with tag 2.0-cm-9.2.1 was released.

It is strongly recommended to fully reindex all documents and Elastic Social data. Refer to section 3.5 Reindexing in the Search Manual for details on how to do that. For CAE Feeders re-indexation, the previous Solr indexes should be deleted altogether after triggering the feeder reset.

Note that re-indexing may take quite some time for large repositories. To avoid long downtime, you can set up a new Content Feeder, new CAE Feeders, and new Solr instance(s) in parallel to your existing installation, connect them to your existing Content Management Server and Master Live Server, and let them feed the indexes of the newly set up Solr instance. During that time, existing Studio and delivery instances will still use the old Solr 8 indexes. When initial feeding is complete, you can update Content Servers, Studio, CAEs, and Headless Servers. They must be configured to use the new Solr instance(s) for search, but will already find an initialized index, so that search is working immediately. Old Content and CAE Feeders as well as old Solr instances can then be shut down. Connecting new Content and CAE Feeders to older Content Servers most likely works, but this needs to be tested individually. Refer to section 3.5.4 Reindexing Content Feeder and CAE Feeder Indices from Scratch / Setup for Reindexing in New Solr in the Search Manual for more information.

During internal tests, upgrading from Solr 8.11.2 without reindexing worked without issues. Solr 8.11.2 was introduced with CoreMedia release 2207.1. Mind, though, that this might not work, if the Solr index had initially been set up using a version prior to Solr 8. If your Solr indexes originate from a Solr version prior to 8, you most likely must start a re-indexation.

Any upgrade scenario must be thoroughly tested for functionality and performance in advance to applying it to a production system. These tests should ideally be performed with a full copy of production data and with real-life usage scenarios, especially with respect to CAE and/or Headless Server delivery.

For details on update planning in custom setups, see https://solr.apache.org/guide/solr/latest/upgrade-notes/major-changes-in-solr-9.html.

Solr 9 introduces "modules" (formerly known as contribs) which have to be enabled to be used (see https://solr.apache.org/guide/solr/latest/upgrade-notes/major-changes-in-solr-9.html and https://solr.apache.org/guide/solr/latest/configuration-guide/solr-modules.html). By default, modules analysis-extras and langid are activated in the CoreMedia Blueprints workspace. If you are using custom configurations that require additional modules, you need to make sure those two are still active.

Please mind that proxy settings for communication of CMS components with Solr 9 are currently not supported.

(CMS-22658)