btrfs-scrub:tldr:2071b

This command initiates a Btrfs scrub on the specified Btrfs filesystem.

Here's a breakdown of the command:

• sudo: It is a command that allows users to run programs with the security privileges of another user, usually as the superuser or root user. It is used here to run the command with administrative privileges.

• btrfs: It is the main command for managing the Btrfs filesystem.

• scrub: It is a subcommand of btrfs used to start a scrub operation on the filesystem. Scrub is a process that scans the entire filesystem, checking for any inconsistencies or errors in data and metadata.

• start: It is an argument for the scrub subcommand, used to initiate the scrub process on the specified Btrfs filesystem.

• -B: This option instructs btrfs scrub to perform a balance operation (metadata balancing) before starting the scrub. The balance operation ensures that metadata is spread evenly across all devices, optimizing performance.

• ${path-to-btrfs_mount}: This is a placeholder for the actual path to the mounted Btrfs filesystem. You need to replace this placeholder with the path to the Btrfs mount point on your system. For example, it could be something like /mnt/btrfs.

In summary, the command sudo btrfs scrub start -B ${path-to-btrfs_mount} is used to start a Btrfs scrub operation with balance on a specific Btrfs filesystem. It helps to detect and fix any inconsistencies or errors in the data and metadata of the filesystem.