Ever since Canonical announced its plans to support ZFS (Zettabyte File System), there has been an abundance of messages from users who say they are infringing the GPL license. More precisely, the ZFS is licensed under CDDL and Linux kernel under GPL v2, which in theory would mean that they can't ship both in the same system.
February 26, 2016
Software Freedom Conservancy Says ZFS Ubuntu Implementation Is Not Legal
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