[Nbd] [NBD]Kernel space and User-space

[harryxiyou <harryxiyou@...17...>]

Hi Wouter and list,

We know nbd has two parts, which are kernel space and user space. So
i have following thoughts, please verify them and answer some questions
about nbd.

1, Nbd kernel space just establishes device node like /dev/nbd*. And it also has
    drivers for nbd. It is related to nbd-client. But i am not sure
the interactions
    between nbd kernel space and nbd-client. Right?

2,  Nbd userspace just do stuffs, which nbd-server give some disk capacities and
    nbd-client receive them with building a device node in kernel
space. Nbd-client
    and Nbd-server communicate with each other over TCP. But i am not sure how
    they send datas and receive them. And if ndb kernel space do some
stuffs during
    this  procedure? If so, what nbd kernel do? Right?

3, I just do following commands.

Server:(ip: 192.168.1.1)
cd /var/tmp
dd if=/dev/zero of=nbd-disk0 bs=1M count=30
nbd-server 1234 /var/tmp/nbd-disk0

Client:
modprobe nbd
sudo nbd-client 192.168.1.1 1234 /dev/nbd0
mkfs.ext3 /dev/nbd0
mkdir file1
mount /dev/nbd0 file1
cp /tmp file1 -rf

Wouter, Cloud you please describe all the details in this procedure
clearly, which
from server's command 'nbd-server' to client's command 'cp'. I just know some
of this process but all in details. I hope you can say some clear
words, which can
understand me. Much thanks to you ;-)


-- 
Thanks
Harry Wei