If you have a database with a system.profile collection and try to back it up with mongodump authenticated as a user with the backup role you get

>mongodump -u backup -p pwd
2015-12-01T19:20:53.419-0500    Failed: error counting test.system.profile: not authorized on test to execute command { count: "system.profile", query: {} }

Either we should give the backup role the ability to back up system.profile collections, or we should modify mongodump to not attempt to back up those collections.