SearchStax Managed Search service users sometimes ask about using Sitecore’s “Switch on Rebuild” feature. This uses a secondary core which can be read while the primary core is being rebuilt.
SWAP vs. CREATEALIAS
Solr’s core swapping depends on its underlying SWAP feature, but SolrCloud uses the CREATEALIAS feature to do the same thing. Using SWAP with SolrCloud can damage your index.
SearchStax Managed Search service deployments are all SolrCloud deployments. Use CREATEALIAS with Managed Search.
Sitecore’s SwitchOnRebuild feature comes in two flavors that mirror the distinction between SWAP and CREATEALIAS. These passages are from Switch SolrCloud Indexes in the Sitecore documentation. Note the distinction between SwitchOnRebuildSolrSearchIndex (for Solr) and SwitchOnRebuildSolrCloudSearchIndex (for SolrCloud):
You use the SwitchOnRebuildSolrSearchIndex class to rebuild and switch Solr indexes. This implementation uses the Solr SWAP command to swap the active and the rebuild indexes.
The mechanism for maintaining and switching two indexes is different when use SolrCloud. The implementation in the SwitchOnRebuildSolrCloudSearchIndex class uses collection aliases: it uses the active alias for search and update operations and the rebuild alias for rebuild operations. When a rebuild operation finishes, the CREATEALIAS command swaps the collections the aliases reference.
So the answer is, “Yes, you can do it.” Just be sure to use the SolrCloud version with Managed Solr.
See the Full Procedure!
Please see our SwitchOnRebuild Blog Article for step-by-step instructions on enabling this feature with Managed Search.
XDB Alias Issues
It is very common to misname the switch-on-rebuild aliases. If you see errors like “‘xdb_rebuild’ is not an existing collection or alias,” revisit the alias names.
Questions?
Do not hesitate to contact the SearchStax Support Desk.