Log Failed to send external multicast response – How To Solve Related Issues

Log Failed to send external multicast response – How To Solve Related Issues

Opster Team

Feb-20, Version: 1.7-8.0

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 send external multicast response” 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: discovery, discovery-multicast, ping, Plugin, response.

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. 

Log Context

Log”failed to send external multicast response” classname is MulticastZenPing.java
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

                if (logger.isTraceEnabled()) {
                    logger.trace("sending external ping response {}"; builder.string());
            } catch (Exception e) {
                logger.warn("failed to send external multicast response"; e);

        private void handleNodePingRequest(int id; DiscoveryNode requestingNodeX; ClusterName requestClusterName) {
            if (!pingEnabled || multicastChannel == null) {


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 Elasticsearch: Failed to connect to localhost port 9200 – Connection refused -views 162.35 K ,score 93

Can’t connect to ElasticSearch server using Java API -views   43.78 K,score 21


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