Re: [Nbd] nbd protocol specification?

[Goswin von Brederlow <goswin-v-b@...186...>]

On Mon, Jan 21, 2013 at 09:08:15AM +0100, Wouter Verhelst wrote:
> On Mon, Jan 14, 2013 at 01:41:34PM +0100, Andreas Klauer wrote:
> > Hi,
> > 
> > I need to implement a block device in user space with my own idea
> > of read and write (like a selective copy-on-write layer). The thing 
> > would be machine-local, network is not important.
> > 
> > I'm currently using FUSE + loop for that, but googling I came across 
> > a [1]BUSE discussion on LKML which in turn referred to NBD. 
> > (never even heard of NBD before... *blush*)
> > 
> > I experimented a bit with it and it seems like an interesting 
> > alternative for me, but to use it, it appears I have to implement 
> > the protocol myself since there doesn't seem to be a C library like 
> > the one FUSE offers? Or is there one I have missed?
> 
> There isn't such a library, indeed. I've been thinking about turning the
> server side of NBD into a library and making nbd-server depend on that
> off and on for a few years, but it just hasn't happened (yet?)

I've been thinking of writing a buse kernel module (like fuse/cuse but
for block devices) on and off for a few years, but it just hasn't
happened (yet?).

Now wouldn't it be great to design the NBD server library in such a
way that it would provide a suitable API for both use cases? After all
buse would just cut out the tcp socket inbetween the server and client
part and communicate with the kernel directly.

MfG
	Goswin