Re: Communicating with the domU from dom0 without Network

[Muli Ben-Yehuda <muli@il.ibm.com>]

On Mon, Aug 07, 2006 at 06:10:15PM +0530, Ligesh wrote:
>  Hi Folks,
> 
>   I would like to have a discussion on whether if it isn't desirable
>   to have some mechanism to directly communicate with the domU from
>   the dom0. Wouldn't that make managing this entire setup much
>   easier? In the openVZ, the vzctl tool can actually run anything
>   inside a virtual machine. For instance, we can say 'vzctl exec
>   $vpsid ps ax', and it will return the output of the 'ps' executed
>   inside the vps. I realize that the virtualization concept is
>   radically different in Xen, and thus this type of communication
>   would be non-trivial.
> 
>   Anyway, I would like to know the pros and cons of having a direct
>   mechanism to communicate with the domUs. As far as I have seen,
>   the inability to manage the domUs directly has been the ONLY
>   drawback of xen. 

I agree this could be useful. If you have networking setup between
dom0 and the domU's (which I think is set up by default), you can do
this without any Xen involvement by just using ssh:

ssh domu.ip.add.ress command args args args

To avoid having ssh ask for a password, use passwordless SSH as
explained in the SSH documentation.

Cheers,
Muli