[Spice-devel] [vdsm] [RFC]about the implement of text-based console

[David Jaša]

Itamar Heim píše v Čt 18. 10. 2012 v 20:32 +0200:
> On 10/18/2012 12:13 PM, Alon Levy wrote:
> >> On 10/16/2012 12:18 AM, David Jaša wrote:
[snip]
> >>> Extending spice to provide just serial console remoting actually
> >>> seems
> >>> the easiest way to provide remote text-only console because most of
> >>> the
> >>> code path is already mature (used for client to guest agent
> >>> communication) and e.g. spicy to just provide a device where e.g.
> >>> screen
> >>> could connect or just provide the console itself.
> >>>
> >>> CCing spice-devel
> >>
> >> would it allow users to script with/over it like they can with ssh?
> >
> > If I understand correctly the idea is to add another channel for spice that would connect to a char device in qemu that in turn connects to a serial port. The result is a spice client that can display and interact, but not a scripting extension. We could also create a unix domain socket to expose this connection on the client, and the client could then use that for scripting (but this will be instead of displaying, since you can't multiplex the console in a meaningful way - unless you run screen/tmux over it maybe):
> >
> > remote-viewer --spice-console-unix-domain-socket /tmp/spice.uds
> > (This option assumes we want a single console channel - if we have multiple we will need to name them too)
> >
> > Anyone will be able to script it using for instance:
> > socat UNIX-CONNECT:/tmp/spice.uds SYSTEM:"echo hello world"
> >
> > We could also turn it into a pty (socat can do that).
> 
> i think using spice this way may be a very good solution, to proxy a 
> serial console.
> only caveat is it requires client to install spice, vs. just using ssh.	

Jarda (To:) actually asked me if this feature (serial device pass
through without any graphics) was feasible for purposes of connecting
remotely to serial console. 
Jarda, would the solution outlined by Alon be good for you?

Alon, one problem comes to my mind though: it would need either second
spice server, or multi-client support (limited one would be enough to
have simultaneously one graphics user and one serial device user). Do
you think it is possible to implement such things without much effort?

David

-- 

David Jaša, RHCE

SPICE QE based in Brno
GPG Key:     22C33E24 
Fingerprint: 513A 060B D1B4 2A72 7F0D 0278 B125 CD00 22C3 3E24