ISO Repository Synchronization fails with Katello::Errors::PulpError: PLP0000

Issue

• ISO Repository Synchronization fails with following error.

 [{"name"=>"rhel-server-6.4-x86_64-dvd.iso", "error"=>{}},
          {"name"=>"rhel-server-6.6-x86_64-dvd.iso", "error"=>{}}]}},
    "queue"=>"reserved_resource_worker-5@satellite.example.com",
    "state"=>"error",
    "worker_name"=>"reserved_resource_worker-5@satellite.example.com",
    "result"=>nil,
    "error"=>
     {"code"=>"PLP0000",
      "data"=>{},
      "description"=>
       "[{'name': u'rhel-server-6.4-x86_64-dvd.iso', 'error': {}}, {'name': u'rhel-server-6.6-x86_64-dvd.iso', 'error': {}}]",
      "sub_errors"=>[]},
    "_id"=>{"$oid"=>"5c6e9e7fafbacxxxxxx"},
    "id"=>"5c6e9e7fafbacb049cxxxxxx"}],
 "contents_changed"=>true,
 "poll_attempts"=>{"total"=>171, "failed"=>1}}

Exception : 
Katello::Errors::PulpError: PLP0000: [{'name': u'rhel-server-6.4-x86_64-dvd.iso', 'error': {}}, {'name': u'rhel-server-6.6-x86_64-dvd.iso', 'error': {}}]