issue of "Log aggregation has not completed or is not enabled."

[ch huang]

hi,maillist:
         i try look application log use the following process

# yarn application -list
                Application-Id      Application-Name
User           Queue                   State
Final-State                             Tracking-URL
application_1395126130647_0014  select user_id as userid,
adverti...stattime(Stage-1)         hive            hive
FINISHED               SUCCEEDED
ch18:19888/jobhistory/job/job_1395126130647_0014
# yarn logs -applicationId application_1395126130647_0014
Logs not available at
/var/log/hadoop-yarn/apps/root/logs/application_1395126130647_0014
Log aggregation has not completed or is not enabled.

but i do enable Log aggregation function ,here is my yarn-site.xml
configuration about log aggregation

  <property>
    <name>yarn.log-aggregation-enable</name>
    <value>true</value>
  </property>
  <property>
    <description>Where to aggregate logs to.</description>
    <name>yarn.nodemanager.remote-app-log-dir</name>
    <value>/var/log/hadoop-yarn/apps</value>
  </property>

the application logs is not put on hdfs successfully,why?

# hadoop fs -ls
/var/log/hadoop-yarn/apps/root/logs/application_1395126130647_0014
ls: `/var/log/hadoop-yarn/apps/root/logs/application_1395126130647_0014':
No such file or directory