btrfs-select-super - Linux

Overview

btrfs-select-super is a command-line utility used to select the preferred root superblock when multiple superblocks exist in a Btrfs file system. It is primarily used during recovery operations or when dealing with complex file system configurations.

Syntax

btrfs-select-super [options] <uuid>

Options/Flags:

  • -f, –force: Force selection even if superblock is in an inconsistent state.
  • -R, –rebuild: Rebuild file system metadata after selecting the new superblock.
  • -n, –no-rebuild: Do not rebuild metadata after selecting the superblock.

Examples

Example 1: Force select a superblock with a specific UUID:

btrfs-select-super -f UUID

Example 2: Select a superblock and rebuild the metadata:

btrfs-select-super -R UUID

Example 3: Select a superblock without rebuilding the metadata:

btrfs-select-super -n UUID

Common Issues

  • Superblock inconsistency: If the selected superblock is in an inconsistent state, the file system may fail to mount. In such cases, use the -f option to force selection.
  • Metadata corruption: If the metadata has been corrupted, selecting a new superblock may not recover all data. You may need to use data recovery tools.

Integration

btrfs-select-super can be used in conjunction with other Btrfs commands, such as:

  • btrfs-inspect: Examine the file system and display information about its superblocks.
  • btrfs-check: Check the file system for errors and inconsistencies.
  • btrfs-restore: Restore a Btrfs file system from a backup.

Related Commands

  • btrfs-inspect
  • btrfs-check
  • btrfs-restore