Hi, We are having an intermittent problem of our indexes being corrupted after a deployment to live. We also experienced this after an environment variable was added to live, which makes me think it’s after an environment restart. We are using Umbraco as a headless CMS and after a deployment to live we are often experiencing no results being returned which is fixed after an examine index rebuild. On the returning events endpoint say, it returned a 200 but with no events found. After we added an environment variable the content delivery api was returning 500s for all endpoints which was fixed after all indexes were rebuilt. I can see in the Umbraco documentation that it advises against using lookups during TransformingIndexEvents and I’m wondering if this is causing our issues. Is there an alternative method for this? Thanks!

Lucene.NET is horrible when it comes to reliability. I absolutely hate these indexes and we're having regular issues with indexes getting corrupted after a deploy. It doesn't happen all the time, but to be honest, I think Umbraco should officially support at least one other option, like ElasticSearch or Solr. Having said that, are you hosting on Azure? If so, make sure you set this correctly: https://docs.umbraco.com/umbraco-cms/fundamentals/setup/server-setup/azure-web-apps

Thank you for your reply! We are hosting on Azure but indirectly as we are on Umbraco cloud, do we still need to look at setting these?