Well, it's like fork but it's the other way. After Oracle bought Sun, other projects that adopted ZFS continued fixing it and adding new features.
So FreeBSD has its version, Illumnos (fork of Solaris) has it own, Delphix own and so on. Those projects were using patches from each other but managing all of that became problematic.
So they basically designated one central place to do ZFS development from which all of the projects will use.
So now instead of many ZFS forks there just two:
- Oracle - which is now closed source
- Open-ZFS - which will be now the official open source ZFS that all Open Source systems will use.
Unfortunately it will still be CDDL, since no one in that project has power to do it. This would require Oracle and all contributors to allow for changing the license.
So FreeBSD has its version, Illumnos (fork of Solaris) has it own, Delphix own and so on. Those projects were using patches from each other but managing all of that became problematic.
So they basically designated one central place to do ZFS development from which all of the projects will use.
So now instead of many ZFS forks there just two: - Oracle - which is now closed source - Open-ZFS - which will be now the official open source ZFS that all Open Source systems will use.
Unfortunately it will still be CDDL, since no one in that project has power to do it. This would require Oracle and all contributors to allow for changing the license.