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Date:   Fri, 14 Jun 2019 12:33:43 +0200
From:   Wouter Verhelst <w@uter.be>
To:     Josef Bacik <josef@toxicpanda.com>
Cc:     Roman Stratiienko <roman.stratiienko@globallogic.com>,
        linux-kernel@vger.kernel.org, nbd@other.debian.org,
        Aleksandr Bulyshchenko <A.Bulyshchenko@globallogic.com>,
        linux-block@vger.kernel.org, axboe@kernel.dkn.org
Subject: Re: [PATCH 2/2] nbd: add support for nbd as root device
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On Thu, Jun 13, 2019 at 10:55:36AM -0400, Josef Bacik wrote:
> Also I mean that there are a bunch of different nbd servers out there.  We have
> our own here at Facebook, qemu has one, IIRC there's a ceph one.

I can't claim to know about the Facebook one of course, but the qemu one
uses the same handshake protocol as anyone else. The ceph ones that I've
seen do too (but there are various implementations of that, so...).

> They all have their own connection protocols.  The beauty of NBD is
> that it doesn't have to know about that part, it just does the block
> device part, and I'd really rather leave it that way.  Thanks,

Sure.

OTOH, there is definitely also a benefit to using the same handshake
protocol everywhere, for interoperability reasons.

-- 
To the thief who stole my anti-depressants: I hope you're happy

  -- seen somewhere on the Internet on a photo of a billboard