Which command is used to change the filesystem type for a device, such as ext3 or ext4?

The command that is used to change the filesystem type for a device, such as ext3 or ext4, is tune2fs. This command is specifically designed for adjusting tunable filesystem parameters on ext2/ext3/ext4 filesystems.

When you want to change the filesystem type, it may not be a straightforward operation, but tune2fs allows certain modifications and configurations related to these filesystems. For example, it can help in changing certain attributes of an ext4 filesystem that would enable features more commonly associated with the filesystem type you want, such as enabling or disabling journaling features.

The other commands do not serve this particular function. For instance, fsck is used for checking and repairing filesystems, but does not change the filesystem type. Similarly, mount is used to mount a filesystem to a specific directory, not to change its type. Resize2fs is used to resize ext2/ext3/ext4 filesystems, but does not alter the filesystem type. Thus, tune2fs is the most suitable choice for changing filesystem parameters and attributes associated with ext2/ext3/ext4.