Which component of Splunk enables the writing of SPL queries to retrieve data?

The component of Splunk that enables the writing of SPL (Search Processing Language) queries to retrieve data is the Search Head. The Search Head is designed specifically for running searches and generating reports on the indexed data. It provides users with an interface where they can create and execute SPL queries to analyze the data collected from various sources.

When a user writes a query using SPL, it is processed by the Search Head, which then communicates with the Indexer to retrieve the relevant indexed data. This architecture allows for efficient searches and data analysis while ensuring that users can interact with the system through a user-friendly interface.

Other components, such as Forwarders and Indexers, play critical roles in data ingestion and storage but do not provide the functionality for writing and executing SPL queries. Forwarders primarily collect and forward data to Indexers, while Indexers store and manage the indexed data but do not directly handle user queries. Heavy Forwarders also focus on data in transit, similar to standard Forwarders, and do not serve as the interface for users to perform searches.