The flume http source is for creating a REST API that you can post data to from the upstream sender. If you are looking for a source that will consume from SQL server via accessing the SQL server API, you'll need to write a custom source for that, or possibly try this: https://github.com/keedio/flume-ng-sql-source

Additionally, if you don't need real time processing, you may want to consider using sqoop to import data via batch processing, and it can handle incremental updates.

-pd