The Error
You are trying to upload your Solr configuration files (schema.xml, solrconfig.xml, and their extras) and the upload fails with errors about missing fields, unknown types, or unresolvable references.
This happens because your config files depend on each other. If you upload schema.xml first but it references types defined in schema_extra_types.xml, Solr cannot understand it — the types do not exist yet.
The Good News
Upload all the files together in one ZIP: Configuration → Upload Config Zip. Opensolr saves every file in the ZIP first and reloads the index once, at the end, so files that depend on each other arrive together and their order does not matter. Files ending in .properties, and files whose names start with a dot or an underscore, are left out of a ZIP upload. More: Upload a ZIP.
Why One File at a Time Fails
Saving a single file in the Configuration tab reloads the index right away. Save schema.xml before the extra file it needs, and that reload fails on the missing reference. Your index keeps its previous configuration, so nothing breaks, but the new schema is not applied. Upload the whole set as one ZIP instead.
Quick Checklist
- Upload every file in one ZIP: Configuration → Upload Config Zip
- Saving files one at a time reloads the index after each one, so a file that needs another one fails
- The index reloads by itself once the ZIP is saved
- Check the Error Log if the reload fails — it will tell you exactly which reference is missing