Starts the indexer for the selected collection. Starts indexing from the root URLs. On reindexing ( clicking on index again after the initial index operation), all crawled document will be reindexed. However, if documents have been deleted from the source website or directory since the first index operation, they will not be deleted from the index. Also, indexing is controlled from the Index sub-tab for a collection or through API. The current status of a collection is always indicated on the Collection Dashboard and the Index page.
Revisits URLs from the current index to make sure they are still valid, and then continues to index newly discovered URLs, modified URLs and deletes the URLs that are not valid. Unmodified URLs (URLs whose last modified date has not changed since the last indexing run) are not reindexed. Refresh can be performed for a collection after Indexing is completed or can be started directly from collections dashboard or via API.