Mapreduce job giving 500 error

I created a MapReduce job using JobDesigner. After submitting the job i am getting below errror

File Name Line Number Function Name
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/build/env/lib/python2.7/site-packages/Django-1.6.10-py2.7.egg/django/core/handlers/base.py 112 get_response
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/build/env/lib/python2.7/site-packages/Django-1.6.10-py2.7.egg/django/db/transaction.py 371 inner
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/apps/oozie/src/oozie/decorators.py 122 decorate
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/apps/oozie/src/oozie/views/editor.py 347 submit_workflow
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/apps/oozie/src/oozie/views/editor.py 368 _submit_workflow
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/desktop/libs/liboozie/src/liboozie/submittion.py 49 decorate
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/desktop/libs/liboozie/src/liboozie/submittion.py 160 deploy
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/desktop/libs/liboozie/src/liboozie/submittion.py 302 _do_as
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/desktop/libs/liboozie/src/liboozie/submittion.py 296 _copy_files
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/desktop/core/src/desktop/lib/fs/proxyfs.py 182 copyfile
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/hue/desktop/libs/hadoop/src/hadoop/fs/webhdfs.py 572 copyfile