Chapter 15. Detecting BitRot

BitRot detection is a technique used in Red Hat Gluster Storage to identify when silent corruption of data has occurred. BitRot also helps to identify when a brick's data has been manipulated directly, without using FUSE, NFS or any other access protocols. BitRot detection is particularly useful when using JBOD, since JBOD does not provide other methods of determining when data on a disk has become corrupt.
The gluster volume bitrot command scans all the bricks in a volume for BitRot issues in a process known as scrubbing. The process calculates the checksum for each file or object, and compares that checksum against the actual data of the file. When BitRot is detected in a file, that file is marked as corrupted, and the detected errors are logged in the following files:
  • /var/log/glusterfs/bitd.log
  • /var/log/glusterfs/scrub.log

15.1. Enabling and Disabling the BitRot daemon

The BitRot daemon is disabled by default. In order to use or configure the daemon, you first need to enable it.
gluster volume bitrot VOLNAME enable
Enable the BitRot daemon for the specified volume.
gluster volume bitrot VOLNAME disable
Disable the BitRot daemon for the specified volume.