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Understanding node services
When a node is running, a lot of services are managed by its instance. Services provide additional functionalities to a node and they cover different behaviors such as networking, indexing, analyzing, and so on.
Getting ready
Every ElasticSearch server that is running provides services.
How it works...
ElasticSearch natively provides a large set of functionalities that can be extended with additional plugins. During a node startup, a lot of required services are automatically started. The most important are as follows:
- Cluster services manage cluster state and intra-node communication and synchronization
- Indexing service manages all the index operations, initializing all active indices and shards
- Mapping service that manages the document types stored in the cluster (we'll discuss mapping in Chapter 3, Managing Mapping)
- Network services, such as HTTP REST services (default on port 9200), internal ES protocol (on port 9300) and Thrift server (on port 9500 if thrift plugin is installed)
- Plugin service (discussed in Chapter 2, Downloading and Setting Up ElasticSearch, for installation and Chapter 12, Plugin Development, for detailed usage)
- River service (covered in Chapter 8, Rivers)
- Language scripting services that allow adding new language scripting support to ElasticSearch