Two properties (that is, fs.default.name and hadoop.http.staticuser.user) need to be set to the etc/hadoop/core-site.xml file. Just copy the following lines of codes:

<configuration>
       <property>
               <name>fs.default.name</name>
               <value>hdfs://localhost:9000</value>
       </property>
       <property>
               <name>hadoop.http.staticuser.user</name>
               <value>hdfs</value>
       </property>
</configuration>