Dual licensing is used to allow developers to choose the license that they believe makes it easiest for them to write their own enhancements and modifications to Gluster.

I don't understand your comment about GPLv2 and LGPLv3 being compatible. GPLv2 and LGPLv3+ have slightly different limitations on what you can do with the Gluster source.

Some organizations find GPLv2 too restrictive. If GPLv2 is too restrictive you have the choice to use LGPLv3+ instead.

If the licensing choices are not clear you should consult your own corporate counsel who are in the best position to give you legal advice.

LGPLv3 is generally understood to be incompatible with code licensed as 'GPLv2 only'. Therefore, by dual-licensing Gluster as (LGPLv3+|GPLv2), it signals that it is compatible with 'GPLv2 only' code.

Some other projects use this form of dual-licensing, for similar reasons; an example I know of offhand is elfutils.

(In reply to Kaleb KEITHLEY from comment #1)
> Dual licensing is used to allow developers to choose the license that they
> believe makes it easiest for them to write their own enhancements and
> modifications to Gluster.
> 
> I don't understand your comment about GPLv2 and LGPLv3 being compatible.
> GPLv2 and LGPLv3+ have slightly different limitations on what you can do
> with the Gluster source.
> 
> Some organizations find GPLv2 too restrictive. If GPLv2 is too restrictive
> you have the choice to use LGPLv3+ instead.
> 
> If the licensing choices are not clear you should consult your own corporate
> counsel who are in the best position to give you legal advice.

Kaleb - thanks for the clarification.  The documentation is unclear that the dual licensing model leaves the choice of whcih license to use to the licensee of the software.  It's worded as GPLv2 AND LGPLv3+.  It would be more clear if it was stated as GPLv2 OR LGPLv3+.  Alternatively, it would be helpful to clearly outline the choice in the documentation. I'm happy to submit a formal request to update the documentation.  

Thanks,
Brian

Could you let us know where you see the AND?

All the license boilerplate in every source file has:

  This file is licensed to you under your choice of the GNU Lesser
  General Public License, version 3 or any later version (LGPLv3 or
  later), _or_ the GNU General Public License, version 2 (GPLv2), in all
  cases as published by the Free Software Foundation.

I'm not a lawyer, but my understanding is that what's actually in the source files is definitive. Other things like (out of date) documentation is not.

If there's some erroneous or misleading documentation somewhere I will try and get it fixed.

Thanks,

Thanks Kaleb. I didn't see the file header. I was working from the github repo.  It lists "and" in the license file comments/summaries.

COPYING-GPLV2	license: dual license under GPLV2 and LGPLV3+	4 years ago
COPYING-LGPLV3	license: dual license under GPLV2 and LGPLV3+	4 years ago

REVIEW: http://review.gluster.org/14872 (license: dual license under GPLV2 _OR_ LGPLV3+) posted (#1) for review on master by Kaleb KEITHLEY (kkeithle)

REVIEW: http://review.gluster.org/14872 (license: dual license under GPLV2 _OR_ LGPLV3+) posted (#2) for review on master by Kaleb KEITHLEY (kkeithle)

Things that github shows, in this case the first line of the last applicable git commit message, are hardly "Documentation" or "The Documentation."

(FYI, the official documentation can be found at http://gluster.readthedocs.io/en/latest/)

Git doesn't have an easy way of revising old commit messages. (Or does it? Can I check out by commit-id, amend, and push? Seems to be of dubious value in any event.) I can't remember anyone else in 4+ years being confused about the license because of a summary shown in a github web page. The actual license is, as indicated above, in each and every source file (where it says ...GPLV2 _OR_ LGPLV3+...), and the files COPYING-GPLV2 and COPYING-LGPLV3 in the source have the terms of those licenses.

Closing. This is not a bug.