Elasticsearch Nodes

By Opster Team

Updated: Jan 28, 2024

| 1 min read

Overview

To put it simply, a node is a single server that is part of a cluster. Each node is assigned one or more roles, which describe the node’s responsibility and operations. Data nodes store the data, and participate in the cluster’s indexing and search capabilities, while master nodes are responsible for managing the cluster’s activities and storing the cluster state, including the metadata.

While it is possible to run several node instances of Elasticsearch on the same hardware, it’s considered a best practice to limit a server to a single running instance of Elasticsearch.

Nodes connect to each other and form a cluster by using a discovery method. 

Roles

Master node

Master nodes are in charge of cluster-wide settings and changes – deleting or creating indices and fields, adding or removing nodes and allocating shards to nodes. Each cluster has a single master node that is elected from the master eligible nodes using a distributed consensus algorithm and is reelected if the current master node fails.

Coordinating (client) node

There is some confusion in the use of coordinating node terminology. Client nodes were removed from Elasticsearch after version 2.4 and became coordinating nodes.

Coordinating nodes are nodes that do not hold any configured role. They don’t hold data and are not part of the master eligible group nor execute ingest pipelines. Coordinating nodes serve incoming search requests and act as the query coordinator running query and fetch phases, sending requests to every node that holds a shard being queried. The coordinating node also distributes bulk indexing operations and route queries to shards based on the node’s responsiveness.

How helpful was this guide?

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?


Related log errors to this ES concept


After allocating node would have less than the required threshold of
After allocating node would have more than the allowed
Remote file corruption on node recovering local checksum OK
Seed node cluster name mismatch expected
Failing snapshot of shard on closed node
Failed to update snapshot state after node removal
Failed to serialize cluster state before publishing it to node
Failed to validate incoming join request from node
Cannot send ban for tasks with the parent to the node
Reload failed for plugin
Attempt to execute a master node operation without task
Node name node ID

< Page: 2 of 22 >