A “400 Error” or “400 Bad Request” error simply means that the Solr server received your request but was unable to make sense of it. It is the HTML code for “something is wrong.”
- A client attempted to use the Solr Config API to change Solr configuration settings. He received a 400 response with notations showing that individual API requests were failing.
SearchStax Solr deployments all run with
-Ddisable.configEdit=true, which directly blocks the Config API. This is a security precaution due to CVE-2020-13957, CVE-2019-17558, and CVE-2019-0192.
See also the similar Why is configset.upload.enabled set to false?
- In the Zookeeper API, the create (create configset) method cannot overwrite an existing configuration of the same name. Solr returns a 400 error in that situation.
- The Solr Schema API will return a 400 error when you attempt to add an existing field to the schema (or add the same field twice).
One often sees generic “Bad Request” errors in the vicinity of other errors indicating that the Solr schema needs to be updated and the content reloaded.