在AWS EMR使用多个Master高可用部署场景下，需要创建3台Master节点上。登录到其中一台节点，运行如下命令：
yarn application -list在某些场景下会遇到如下报错。报错信息：
WARN ipc.Client: Failed to connect to server: ip-172-31-22-134.cn-northwest-1.compute.internal/172.31.22.134:8032: retries get failed due to exceeded maximum allowed retries number: 0
java.net.ConnectException: Connection refused