Re: [Qemu-devel] [PATCH for-4.0 00/14] nbd: add qemu-nbd --list

["Richard W.M. Jones" <rjones@redhat.com>]

On Fri, Nov 30, 2018 at 04:03:29PM -0600, Eric Blake wrote:
> I note that upstream NBD has 'nbd-client -l $host' for querying
> just export names (with no quoting, so you have to know that
> a blank line means the default export), but it wasn't powerful
> enough, so I implemented 'qemu-nbd -L' to document everything.
> Upstream NBD has separate 'nbd-client' and 'nbd-server' binaries,
> while we only have 'qemu-nbd' (which is normally just a server,
> but 'qemu-nbd -c' also operates a second thread as a client).
> Our other uses of qemu as NBD client are for consuming a block
> device (as in qemu-io, qemu-img, or a drive to qemu) - but those
> binaries are less suited to something so specific to the NBD
> protocol.

I tried it against nbdkit and it works (obviously):

$ ./qemu-nbd -L 
exports available: 1
 export: ''
  size:  67108864
  flags: 0x61 ( trim zeroes )

What I couldn't work out is how to connect to other hosts.  It's
possible to add -p or -k to change the localhost port number or to use
a Unix domain socket (and I checked both work).  However can we
connect to remote hosts?

Rich.

-- 
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