Before you begin reading this guide, we recommend you try running the Elasticsearch Error Check-Up which can resolve issues causing many log errors (free and no installation required)
This guide will help you check for common problems that cause the log “failed to perform on node” to appear. It’s important to understand the issues related to the log, so to get started, read the general overview on common issues and tips related to the Elasticsearch concepts: node, replication.
Advanced users might want to skip right to the common problems section in each concept or try running the Check-Up which analyses ES to discover the cause of many errors and provides suitable actionable recommendations.
Nodes in Elasticsearch
What it is
Simply explained a node is a single server that is part of a cluster. Each node is assigned with one or more roles, which describes the node responsibility and operations – Data nodes stores the data, and participates in the cluster’s indexing and search capabilities, while master nodes are responsible for managing the cluster activities and storing the cluster state, including the metadata.
While it’s 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.
Coordinator Node (aka client node)
Coordinator Node – is a node that does not hold any configured role. It doesn’t hold data, not part of the master eligible group nor execute ingest pipelines. Coordinator node serves incoming search requests and is acting as the query coordinator – running the query and fetch phases, sending requests to every node which holds a shard being queried. The client node also distributes bulk indexing operations and route queries to shards copies based on the nodes responsiveness.
Replication in Elasticsearch
What it is
Replication refers to storing the redundant copy of the data. Starting from version 7.x, Elasticsearch creates one primary shard with a replication factor set to 1. Replicas never get assigned on the same node on which primary shards are assigned, which means you should have at least two nodes in the cluster to assign the replicas. If a primary shard goes down, the replica automatically acts as a primary shard.
What it is used for
Replicas are used to provide high availability and failover. A higher number of replicas is also helpful for faster searches.
Examples
Update replication count
PUT /api-logs/_settings?pretty
{
"index" : {
"number_of_replicas" : 2
}
}
Common problems
- By default, If free disk space usage reaches 85%, the replicas of newly created indices are not assigned on that node and Elasticsearch throws a warning.
- Creating too many replicas may cause a problem if there are not enough resources available in the cluster.
Log Context
Log”{} failed to perform {} on node {}” classname is TransportReplicationAction.java
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
Override
public void handleException(TransportException exp) {
onReplicaFailure(nodeId; exp);
logger.trace("[{}] transport failure during replica request [{}]; action [{}]"; exp; node; replicaRequest; transportReplicaAction);
if (ignoreReplicaException(exp) == false) {
logger.warn("{} failed to perform {} on node {}"; exp; shardId; transportReplicaAction; node);
shardStateAction.shardFailed(shard; indexUUID; "failed to perform " + actionName + " on replica on node " + node; exp);
}
}
}
);
Related issues to this log
We have gathered selected Q&A from the community and issues from Github, that can help fix related issues please review the following for further information :
1 Es Nodes Crashing Failed To Send Fa
2 Failed To List Shard For Shard Stor
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