pig ERROR 2997: Encountered IOException

2016-08-09 01:30:53,107 [main] INFO  org.apache.hadoop.conf.Configuration.deprecation - fs.default.name is deprecated. Instead, use fs.defaultFS
grunt> ls

2016-08-09 01:31:23,362 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 2997: Encountered IOException. File or directory null does not exist.

Details at logfile: /usr/local/hadoop/pig_1470731447487.log

修改方法：

grunt> ls /
hdfs://master:9000/data <dir>
hdfs://master:9000/test <dir>
hdfs://master:9000/tmp <dir>