How to configure GlusterFS bitrot scrub settings

Tuning GlusterFS bitrot scrubbing reduces the risk of silent data corruption by controlling how often integrity checks run and how much IO is consumed while scanning. Conservative settings keep verification running in the background without turning routine workloads into an accidental stress test.

When bitrot is enabled on a volume, GlusterFS maintains file signatures and periodically scrubs bricks to compare stored signatures against computed checksums. The scrub schedule is controlled by the scrub frequency, while scrub throttle limits how aggressively the scrubber consumes disk and CPU resources.

Scrubbing competes with client reads and writes, especially on busy volumes or when the throttle is increased. Frequency and throttle are configured per volume, so different volumes can be tuned to match workload patterns and maintenance windows.

Steps to configure GlusterFS bitrot scrub settings:

Set the scrub throttle mode for the volume.
```
$ sudo gluster volume bitrot volume1 scrub-throttle normal
```
Valid values: lazy, normal, aggressive.

Using aggressive increases scrub IO and can noticeably impact client performance during scrubs.
Set the scrub frequency for the volume.
```
$ sudo gluster volume bitrot volume1 scrub-frequency weekly
```
Valid values: daily, weekly, biweekly, monthly.

Confirm the configured scrub settings for the volume.

$ sudo gluster volume get volume1 all | grep -E 'features\.(bitrot|scrub)'
Option: features.bitrot Value: on
Option: features.scrub-freq Value: weekly
Option: features.scrub-throttle Value: normal

Replace volume1 with the target volume name.

Pause scrubbing during peak load when required.
```
$ sudo gluster volume bitrot volume1 scrub pause
```
Signing continues even when scrubbing is paused.

Resume scrubbing after the maintenance window.

$ sudo gluster volume bitrot volume1 scrub resume

Verify scrub status for the volume.
```
$ sudo gluster volume bitrot volume1 scrub status
Scrubber status: Active
```
Output varies by GlusterFS version and volume state.

Author: Mohd Shakir Zakaria
Mohd Shakir Zakaria is a cloud architect with deep roots in software development and open-source advocacy. Certified in AWS, Red Hat, VMware, ITIL, and Linux, he specializes in designing and managing robust cloud and on-premises infrastructures.