我正在尝试将我的5节点hadoop集群从1.0升级到2.2.0。当我尝试使用hadoop-daemon.sh start namenode-upgrade命令升级namenode并检查日志文件时，我得到以下错误消息。

015-03-13 10:02:24,549 FATAL org.apache.hadoop.hdfs.server.namenode.NameNode: Exception in namenode join
    java.lang.IllegalArgumentException: Invalid URI for NameNode address (check fs.defaultFS): file:/// has no authority.
            at org.apache.hadoop.hdfs.server.namenode.NameNode.getAddress(NameNode.java:347)
            at org.apache.hadoop.hdfs.server.namenode.NameNode.getAddress(NameNode.java:335)
            at org.apache.hadoop.hdfs.server.namenode.NameNode.getRpcServerAddress(NameNode.java:388)
            at org.apache.hadoop.hdfs.server.namenode.NameNode.loginAsNameNodeUser(NameNode.java:471)
            at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:483)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:684)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:669)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1254)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1320)
2015-03-13 10:02:24,586 INFO org.apache.hadoop.util.ExitUtil: Exiting with status 1
2015-03-13 10:02:24,593 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: SHUTDOWN_MSG:
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at nn.cluster.com/192.168.1.75

************************************************************/