Before you begin reading this guide, we recommend you run Elasticsearch Error Check-Up which analyzes 2 JSON files to detect many errors.
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This guide will help you check for common problems that cause the log ” Error closing netty event loop group ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: netty.
Log Context
Log “Error closing netty event loop group” classname is Netty4Transport.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
protected void stopInternal() {
Releasables.close(() -> {
Future> shutdownFuture = eventLoopGroup.shutdownGracefully(0; 5; TimeUnit.SECONDS);
shutdownFuture.awaitUninterruptibly();
if (shutdownFuture.isSuccess() == false) {
logger.warn("Error closing netty event loop group"; shutdownFuture.cause());
}
serverBootstraps.clear();
clientBootstrap = null;
});
