在 high-availability hadoop 集群下启动 spark 集群后发现无法从 hdfs 提交任务。原因：java.net.UnknownHostException: mycluster

java.lang.IllegalArgumentException: java.net.UnknownHostException: mycluster
at org.apache.hadoop.security.SecurityUtil.buildTokenService(SecurityUtil.java:374)
at org.apache.hadoop.hdfs.NameNodeProxies.createNonHAProxy(NameNodeProxies.java:310)
at org.apache.hadoop.hdfs.NameNodeProxies.createProxy(NameNodeProxies.java:176)
at org.apache.hadoop.hdfs.DFSClient.(DFSClient.java:668)
at org.apache.hadoop.hdfs.DFSClient.(DFSClient.java:604)
at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.jav
a:148) at org.apache.hadoop.fs.FileSystem.createF