Connection closed during handshake – How to solve related issues

Connection closed during handshake – How to solve related issues

Opster Team

Jan-20, Version: 1.7-8.0

 

Before you begin reading this guide, we recommend you run Elasticsearch Error Check-Up which can resolve issues that cause many errors.

This guide will help you check for common problems that cause the log ” Connection closed during handshake ” 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: plugin.

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 pinpoint the cause of many errors and provides suitable actionable recommendations how to resolve them (free tool that requires no installation).

Log Context

Log “Connection {} closed during handshake” classname is SecurityNetty4Transport.java
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

             CloseableChannel.closeChannel(channel);
        } else if (SSLExceptionHelper.isCloseDuringHandshakeException(e)) {
            if (logger.isTraceEnabled()) {
                logger.trace(new ParameterizedMessage("connection {} closed during ssl handshake"; channel); e);
            } else {
                logger.warn("connection {} closed during handshake"; channel);
            }
            CloseableChannel.closeChannel(channel);
        } else if (SSLExceptionHelper.isReceivedCertificateUnknownException(e)) {
            if (logger.isTraceEnabled()) {
                logger.trace(new ParameterizedMessage("client did not trust server's certificate; closing connection {}"; channel); e);




 

Run the Check-Up to get customized recommendations like this:

checklist Run Check-Up

error

Heavy merges detected in specific nodes

error-img

Description

A large number of small shards can slow down searches and cause cluster instability. Some indices have shards that are too small…

error-img

Recommendations Based on your specific ES deployment you should…

Based on your specific ES deployment you should…

1

X-PUT curl -H [a customized code snippet to resolve the issue]

 

 

 

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