Reloading a Solr core

Reload a Solr core instead of creating a new one when you modify the schema.xml or solrconfig.xml.

Reload a Solr core instead of creating a new one when you modify the schema.xml or solrconfig.xml.
$ curl "http://localhost:8983/solr/admin/cores?action=RELOAD&name=keyspace.table"

You can use options with the RELOAD command to re-index and keep, or delete, the Lucene index. When you do not specify an option, the default is used. Changes apply only to the node where you reload the core.

When you make a change to the schema, the compatibility of the existing index and the new schema is questionable. If the change to the schema made changes to a field's type, the index and schema will certainly be incompatible. Changes to a field's type can actually occur in subtle ways, occasionally without a change to the schema.xml file itself. For example, a change to other configuration files, such as synonyms, can change the schema. If such an incompatibility exists, a full re-index, which includes deleting all the old data, of the Solr data is required. In these cases, anything less than a full re-index renders the schema changes ineffective. Typically, a change to the Solr schema requires a full re-indexing.

Use these RELOAD command options to specify the level of re-indexing that occurs:
  • distributed

    True, the default, distributes an index to nodes in the cluster. False re-indexes the Solr data on one node. The false setting is used in certain recovery and upgrade procedures.

    $ curl -v "http://localhost:8983/solr/admin/cores?action=RELOAD&
  name=keyspace.table&distributed=false"
  • reindex and deleteAll

    Re-indexes data in place or re-indexes in full. The default for both options is false. Accepting the defaults reloads the core and no re-indexing occurs.

Re-indexing in place

Setting reindex=true and deleteAll=false re-indexes data and keeps the existing lucene index. During the uploading process, user searches yield inaccurate results. To perform an in-place re-index, use this syntax:
curl "http://localhost:8983/solr/admin/cores?action=RELOAD
  &name=keyspace.table&reindex=true&deleteAll=false"

Re-indexing in full

Setting reindex=true and deleteAll=true deletes the Lucene index and re-indexes the dataset. User searches initially return no documents as the Solr cores reload and data is re-indexed.

Setting reindex=false and deleteAll=true does nothing and generates an exception.