dtrace
ZFS

So, if you feel that there is a licensing issue with ZFS, please feel free to write to Apple and tell them to yank out dtrace as well. Because, guess what – you can type “man dtrace” on Mountain Lion and get some interesting things to read.

It was *NOT* a licensing issue, it was an indemnity issue, and Apple asked Sun to indemnify them against any lawsuits arising from their use of ZFS, and Sun said no.

There is no reason whatsoever for anyone to stop dealing with ZFS, and the GPL and Linux have a completely different issue. ZFS can work perfectly fine and without dispute on Linux as long as ZFS is not distributed inside the kernel’s GPL source code, but even its direct legal inclusion is debated. And finally, ZFS is not a bandwagon; it’s sheer technological superiority and necessity.

In the meantime, ZFS is free software, it’s not dependent upon any company or person, and it’s always been on Mac OS at http://maczfs.org/ . Thanks!

ZFS uses the Common Development and Distribution License. Apple uses Apple Public Source License which is based on GNU. GNU and CDDL are not compatible with each other. This is from http://www.gnu.org/licenses/license-list.html:

“This is a free software license. It has a copyleft with a scope that’s similar to the one in the Mozilla Public License, which makes it incompatible with the GNU GPL. This means a module covered by the GPL and a module covered by the CDDL cannot legally be linked together. We urge you not to use the CDDL for this reason.

Also unfortunate in the CDDL is its use of the term “intellectual property”.”

Here is a good write up about ZFS and Linux licensing, http://kerneltrap.org/node/8066. ZFS and Apple would have similar issues. That is the real reason Apple did not adopt ZFS.

This is not the first time Apple has run into licensing issues when implementing technology. Apple’s printing technology is based on CUPS. Ever consider funny why Apple bought CUPS? It comes down to licensing. CUPS, at the time, could have changed their licensing to GPLv3, which is a digital rights mess, forcing Apple’s hand as it pertained to CUPS. It was much easier to just buy CUPS to insure it stayed GPLv2.

There are available ZFS solutions for the Mac. Those companies distributing ZFS are not as encumbered by the CDDL agreement. The CDDL is not as much a detriment to them as it would be to Apple.

So, in recap, licensing sometimes gets in the way of a company being able to adopt technology. It is Sun’s Licensing agreement that gets in the way of a true wider adoption of ZFS. Apple just didn’t decide to not adopt ZFS, they couldn’t get licensing ironed out.