【Hadoop】Call to localhost/127.0.0.1:8020 failed on connection exception

运行命令hadoop fs -copyFromLocal ~/log hdfs://localhost/user/wrf/log后，出现Call to localhost/127.0.0.1:8020 failed on connection exception：Connection refused的错误

14/07/02 14:31:57 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 0 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:31:58 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 1 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:31:59 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 2 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:32:00 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 3 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:32:01 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 4 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:32:02 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 5 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:32:03 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 6 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:32:04 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 7 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:32:05 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 8 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/07/02 14:32:06 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8020. Already tried 9 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
copyFromLocal: Call to localhost/127.0.0.1:8020 failed on connection exception: java.net.ConnectException: Connection refused

用jps查看namenode和datanode，发现进程都存在，而且命令hadoop fs -ls /正常运行。

最后发现由于在core-site.xml中将fs.default.name设置成了hdfs://192.168.10.201:9000，只需要把端口号由9000改为8020后，然后重新启动集群，就可以运行了。