2016-04-09 20:26:31,887 - Error while executing command 'start':
Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/resource_management/libraries/script/script.py", line 214, in execute
    method(env)
  File "/var/lib/ambari-agent/cache/common-services/YARN/2.1.0.2.0/package/scripts/resourcemanager.py", line 60, in start
    action='start'
  File "/var/lib/ambari-agent/cache/common-services/YARN/2.1.0.2.0/package/scripts/service.py", line 59, in service
    initial_wait=5
  File "/usr/lib/python2.6/site-packages/resource_management/core/base.py", line 148, in __init__
    self.env.run()
  File "/usr/lib/python2.6/site-packages/resource_management/core/environment.py", line 152, in run
    self.run_action(resource, action)
  File "/usr/lib/python2.6/site-packages/resource_management/core/environment.py", line 118, in run_action
    provider_action()
  File "/usr/lib/python2.6/site-packages/resource_management/core/providers/system.py", line 274, in action_run
    raise ex
Fail: Execution of 'ls /var/run/hadoop-yarn/yarn/yarn-yarn-resourcemanager.pid >/dev/null 2>&1 && ps -p `cat /var/run/hadoop-yarn/yarn/yarn-yarn-resourcemanager.pid` >/dev/null 2>&1' returned 1.