About managing indexes
When you add data, the indexer processes it and stores it in an index. By default, data you feed to an indexer is stored in the main index, but you can create and specify other indexes for different data inputs.
An index is a collection of directories and files. These are located under
$SPLUNK_HOME/var/lib/splunk. Index directories are also called buckets and are organized by age. For information on index storage, see How Splunk Enterprise stores indexes.
In addition to the main index, Splunk Enterprise comes preconfigured with a number of internal indexes. Internal indexes are named starting with an underscore (_). To see a full list of indexes in Splunk Web, click the Settings link in the upper portion of Splunk Web and then select Indexes. The list includes:
- main: The default Splunk Enterprise index. All processed external data is stored here unless otherwise specified.
- _internal: This index includes Splunk Enterprise internal logs.
- _metrics: This index contains Splunk Enterprise internal data, stored in the form of metric data points.
- _audit: Events from the file system change monitor, auditing, and all user search history.
- _introspection: This index provides data about the Splunk Enterprise instance and environment .
A number of topics in this manual describe ways you can manage your indexes. In particular, the following topics are helpful in index management:
- Create custom indexes
- Remove indexes and data from Splunk
- Configure index storage
- Move the index database
- Use multiple partitions for index data
- Configure index size
- Set limits on disk usage
- Back up indexed data
- Set a retirement and archiving policy
Splunk Enterprise supports two types of indexes:
- Events indexes. Events indexes impose minimal structure and can accommodate any type of data, including metrics data. Events indexes are the default index type.
- Metrics indexes. Metrics indexes use a highly structured format to handle the higher volume and lower latency demands associated with metrics data. Putting metrics data into metrics indexes results in faster performance and less use of index storage, compared to putting the same data into events indexes. For information on the metrics format, see the Metrics manual.
There are minimal differences in how indexers handle the two index types. Any differences that do exist are described in the relevant topic.
For more information about the indexing process
To learn more about indexes, see:
- The topic How indexing works in this manual.
- The topic How Splunk stores indexes in this manual.
- The chapter About clusters and index replication in this manual.
- The chapter Configure event processing in Getting Data In.
- The chapter Set up and use summary indexes in the Knowledge Manager Manual, for information about working with extremely large datasets.
Indexers in a distributed deployment
Create custom indexes
This documentation applies to the following versions of Splunk® Enterprise: 8.0.4, 8.0.5, 8.0.6, 8.0.7, 8.0.8, 8.0.9, 8.1.0, 8.1.1, 8.1.2, 8.1.3, 8.1.4, 8.2.0