in flume-elasticsearch-sink/src/main/java/org/apache/flume/sink/elasticsearch/client/ElasticSearchTransportClient.java [193:207]
private void openClient(String clusterName) {
logger.info("Using ElasticSearch hostnames: {} ",
Arrays.toString(serverAddresses));
Settings settings = ImmutableSettings.settingsBuilder()
.put("cluster.name", clusterName).build();
TransportClient transportClient = new TransportClient(settings);
for (InetSocketTransportAddress host : serverAddresses) {
transportClient.addTransportAddress(host);
}
if (client != null) {
client.close();
}
client = transportClient;
}