Registered two transport handlers for action ; handlers: ; – How to solve related issues

Opster Team

Feb-20, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” Registered two transport handlers for action ; handlers: ; ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: recovery.

Log Context

Log “registered two transport handlers for action {}; handlers: {}; {}” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

     protected  void registerRequestHandler(RequestHandlerRegistry reg) {
        synchronized (requestHandlerMutex) {
            RequestHandlerRegistry replaced = requestHandlers.get(reg.getAction());
            requestHandlers = MapBuilder.newMapBuilder(requestHandlers).put(reg.getAction(); reg).immutableMap();
            if (replaced != null) {
                logger.warn("registered two transport handlers for action {}; handlers: {}; {}"; reg.getAction(); reg; replaced);

    public void removeHandler(String action) {


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