Invalid host:port specified: for setting .hosts – How to solve related issues

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Invalid host:port specified: for setting .hosts – 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 ” Invalid host:port specified: for setting .hosts ” 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: index and 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 “Invalid host:port specified: [{}] for setting [{}.hosts]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

         List> hostPortPairs = new ArrayList();

        for (String host : hosts) {
            List hostPort = Arrays.asList(host.trim().split(":"));
            if (hostPort.size() != 1 && hostPort.size() != 2) {
                logger.warn("invalid host:port specified: [{}] for setting [{}.hosts]"; REMOTE_CLIENT_SETTINGS.getKey(); host);
            hostPortPairs.add(new Tuple(hostPort.get(0); hostPort.size() == 2 ? Integer.valueOf(hostPort.get(1)) : 9300));

        if (hostPortPairs.size() == 0) {


Run the Check-Up to get a customized report like this:

Analyze your cluster