Components of a Splunk deployment
Splunk is simple to deploy by design. By using a single software component and easy to understand configurations, Splunk can coexist with existing infrastructure or be deployed as a universal platform for accessing machine data.
The simplest deployment is the one you get by default when you install Splunk: indexing and searching on the same server. Data comes in from the sources you've configured, and you log into Splunk Web or the CLI on this same server to search, monitor, alert, and report on your machine data.
Depending on your needs, you can also deploy components of Splunk on different servers to address your load and availability requirements. This section introduces the types of components. For a more thorough introduction, including diagrams of typical Splunk distributed topologies, see the Distributed Deployment manual, particularly the topics, "Distributed Splunk overview" and "Scale your deployment: Splunk components".
Splunk indexers, or index servers, provide indexing capability for local and remote data and host the primary Splunk data store, as well as Splunk Web. Refer to "How indexing works" in the Admin manual for more information.
A search head is a Splunk instance configured to distribute searches to indexers, or search peers. Search heads can be either dedicated or not, depending on whether they also perform indexing. Dedicated search heads don't have any indexes of their own (other than the usual internal indexes). Instead, they consolidate results originating from remote search peers.
See "About distributed search" in the Distributed Deployment Manual to learn how to configure a search head to search across a pool of indexers.
Forwarders are Splunk instances that forward data to remote indexers for indexing and storage. In most cases, they do not index data themselves. Refer to the "About forwarding and receiving" topic in the Distributed Deployment manual for additional information on forwarders.
Both indexers and forwarders can also act as deployment servers. A deployment server distributes configuration information to running instances of Splunk via a push mechanism which is enabled through configuration. Refer to "About deployment server" for additional information.
Functions at a glance
|Functions||Indexer||Search head||Forwarder||Deployment server|
|Forward to indexer||x|
Hardware capacity planning for your Splunk deployment
This documentation applies to the following versions of Splunk® Enterprise: 4.3, 4.3.1, 4.3.2, 4.3.3, 4.3.4, 4.3.5, 4.3.6, 4.3.7