Why is my Application Reporting 'File exists' Errors When Running on the Top of a Gluster File System?

Issue

• A Redis application reports File exists errors when moving some temporary files to their final destination:

  Error moving temp DB file temp-857.rdb on the final destination dump.rdb (in server root dir /var/app/redis/data): File exists
  

• The directory /var/app/redis/data comes from a Gluster mount point:

  10.00.00.1:vol_gluster                                                2.0G  1.1G  945M  54% /var/app/redis/data
  

• Why are these errors occurring and how to fix them?