# Specifying a default data source

Among the data sources in your Discovery Framework application, you must always include a default data source. This data source is automatically assigned to all data-source-backed components when they are initially added to a page.

When you initially start the Discovery Framework, the id of this data source is default. While this setting remains unchanged, you must include a data source with the id default. Upon installation, a default.json data source file (with an implicit id of default) is included in the endeca-portal\data\endeca-data-sources directory.

Alternatively, you can change the default data source name to that of another data source file. To do so:

1. In the Liferay Control Panel, go to the Discovery Framework Settings page.
2. In the Discovery Framework Settings page, change the df.defaultDataSource setting to a different value.
3. Restart the Discovery Framework.
4. Make sure you include a data source with that new value as its id.