Connection failed to node at – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 6.8-8.9

Briefly, this error occurs when Elasticsearch cannot establish a connection to a specific node. This could be due to network issues, incorrect configuration settings, or the node being down. To resolve this, you can check the network connectivity between the nodes, verify the node’s IP address and port in the configuration file, and ensure the node is running and accessible. If the issue persists, you may need to restart the node or the entire Elasticsearch cluster.

This guide will help you check for common problems that cause the log ” connection failed to node at [{}://{}:{}] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin, node.

Log Context

Log “connection failed to node at [{}://{}:{}]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :


    public void onFailure(final Node node) {
        HttpHost host = node.getHost();
        logger.warn("connection failed to node at [{}://{}:{}]"; host.getSchemeName(); host.getHostName(); host.getPort());

        final HttpResource resource = this.resourceHolder.get();
        final Sniffer sniffer = this.snifferHolder.get();

        if (resource != null) {