ZFS™ (Z file system) is a combined file system and logical volume manager designed by Sun Microsystems.
Fedora releases don't ship proper ZFS support included to kernel because its license CDDL (Common Development and Distribution License), instead it's available as a FUSE (Filesystem in Userspace) module (pacakge name zfs-fuse).
- opensolaris.org/os/community/zfs/ Oracle's ZFS
- zfsonlinux.org - The native Linux kernel port of the ZFS filesystem
- zfs-fuse.net - ZFS-FUSE project