From owner-freebsd-virtualization@freebsd.org  Wed Dec  6 17:48:06 2017
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From: "Rodney W. Grimes" <freebsd-rwg@pdx.rh.CN85.dnsmgr.net>
Message-Id: <201712061748.vB6Hm13h057501@pdx.rh.CN85.dnsmgr.net>
Subject: Re: NFS alternatives (was: Re: Storage overhead on zvols)
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To: "Patrick M. Hausen" <hausen@punkt.de>
Date: Wed, 6 Dec 2017 09:48:01 -0800 (PST)
CC: Paul Vixie <paul@redbarn.org>,
 FreeBSD virtualization <freebsd-virtualization@freebsd.org>
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> Hi all,
> 
> > Am 05.12.2017 um 17:41 schrieb Rodney W. Grimes <freebsd-rwg@pdx.rh.CN85.dnsmgr.net>:
> > In effect what your asking for is what NFS does, so use NFS and get
> > over the fact that this is the way to get what you want.  Sure you
> > could implement a virt-vfs but I wonder how close the spec of that
> > would be to the spec of NFS.
> 
> I figure it should be possible to implement something simpler
> than NFS that provides full local posix semantics under the
> constraint that only one "client" is allowed to mount the FS
> at a time.
> 
> I see quite a few applications for something like this, specifically
> in "hyperconvergent" environments. Or vagrant, of course.
> 
> *scratching head* isn't this what Sun's "network disk" protocol provided?

nd provided a 512b block device, no file system symatics at all,
I believe it did allow 1 writer N readers though.

Today you would use iSCSI in place of nd.

-- 
Rod Grimes                                                 rgrimes@freebsd.org