HDFS Client UnknownHostException: NAMESERVICE

原始文章链接：https://alphablacktan.github.io/bigdata/2018/08/12/HDFS-Client-UnknownHostException-NAMESERVICE/

问题现象

HDFS Client抛出如下异常：

java.net.UnknownHostException: NAMESERVICE
	at org.apache.hadoop.security.SecurityUtil.buildTokenService(SecurityUtil.java:374)
	at org.apache.hadoop.hdfs.NameNodeProxies.createNonHAProxy(NameNodeProxies.java:312)
	at org.apache.hadoop.hdfs.NameNodeProxies.createProxy(NameNodeProxies.java:178)
	at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:665)
	at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:601)

问题分析

Configuration实例缺乏配置项dfs.client.failover.proxy.provider.NAMESERVICE。

问题解决方案

在Configuration实例或其加载的配置文件中添加对应配置项。