I have set an incremental crawl rule to execute an incremental crawl every 20 minutes. But my question is do I need to perform a full crawl, beside the incremental crawl ? Regards
A full crawl is needed to collect the items the incrementals don't catch. Items like manage properties and security updates on file shares are not considered in incremental searches. Also, a full crawl reindexes everything, therefore rebuilding the entire index, which can help reduce the chance of having a corrupted index. Because a full crawl take a lot more time and resources, I usually set them up nightly or weekly at 11p - 1a, depending on other factors (backups, amount of data, other system routines, etc).