Multiple PVM consoles

Multiple PVM consoles

[Steve Brueckner]

A colleague of mine asked this question on xen-users, but it may be more of
a developer question.  We need to make multiple independent console
connections to a paravirtualized VM (not 2 windows sharing a single
console), and without using the network (no telnet or ssh solutions).
Searching the archives I've found about 6 threads discussing this, among
them:

This one, which says it was on the roadmap for versions 2 and/or 3:
http://lists.xensource.com/archives/html/xen-devel/2006-07/msg00424.html
> Currently, each PV guest is allowed just a single virtual serial 
> console device. Although once we have PV framebuffer support (and 
> associated virtual terminals) virtual serial console support will be 
> less important, it would still be nice to support multiple consoles 
> per guest. This should be relatively straight forward, requiring 
> updates to the console frontend driver, xenconsoled, and the tools.
> ...
> 2/3   & linux         & support for multiple virtual serial consoles

And these, opening the possibility of 2 consoles (on the paravirt
framebuffer and on a virtual serial port):
http://lists.xensource.com/archives/html/xen-devel/2006-08/msg00170.html
http://lists.xensource.com/archives/html/xen-devel/2006-09/msg00072.html

Can anyone tell me if and when it will be possible to get 2 independent
consoles into a paravirtualized guest?  Or will the kernel always have only
one input/output stream, resulting in behavior similar to the "multiple
windows to a shared console" scenario we have now?

Thanks,

 - Steve

Stephen Brueckner, ATC-NY

Re: Multiple PVM consoles

[Anthony Liguori]

On Thu, 14 Sep 2006 11:21:59 -0400, Steve Brueckner wrote:

> A colleague of mine asked this question on xen-users, but it may be more
> of a developer question.  We need to make multiple independent console
> connections to a paravirtualized VM (not 2 windows sharing a single
> console), and without using the network (no telnet or ssh solutions).
> Searching the archives I've found about 6 threads discussing this, among
> them:
> 
> This one, which says it was on the roadmap for versions 2 and/or 3:
> http://lists.xensource.com/archives/html/xen-devel/2006-07/msg00424.html
>> [quoted text muted]
> 
> And these, opening the possibility of 2 consoles (on the paravirt
> framebuffer and on a virtual serial port):
> http://lists.xensource.com/archives/html/xen-devel/2006-08/msg00170.html
> http://lists.xensource.com/archives/html/xen-devel/2006-09/msg00072.html
> 
> Can anyone tell me if and when it will be possible to get 2 independent
> consoles into a paravirtualized guest?  Or will the kernel always have
> only one input/output stream, resulting in behavior similar to the
> "multiple windows to a shared console" scenario we have now?

This feature has been discussed repeated but AFAIK noone has stepped up to
actually implement it.

Regards,

Anthony Liguori

> Thanks,
> 
>  - Steve
> 
> Stephen Brueckner, ATC-NY