From Fedora Project Wiki

Description

Migrating a filesystem from Ext4 (or other) to btrfs. NOTE: Convert has been rewritten since btrfs-progs 4.6; and rollback has been reworked in btrfs-progs 4.10.1. See https://btrfs.wiki.kernel.org/index.php/Conversion_from_Ext3 for more info.


How to test

  1. Create an ext4 partition
  2. Dump some data on it (large and small files)
  3. yum install btrfs-progs
  4. unmount the ext4 filesystem to be migrated
  5. Run btrfs-convert on the partition
  6. Mount partition
  7. Verify if files are still a) present and b) sane.
  8. Verify if a backup snapshot is created (TODO: Verify that this is default behavior)


Expected Results

  1. btrfs-progs install successfully
  2. btrfs-convert runs successfully
  3. Data should be present and sane