[Libvir] A question about libvirt usage

[Daniel Veillard]

On Tue, Jun 13, 2006 at 05:10:27PM +0200, Philippe Berthault wrote:
> Is there a notion of session in libvirt ?
> 
> In other words, is it possible, between virConnectOpen() and 
> virConnectClose(), that some Xen domains will be started, stopped, 
> destroyed, etc.. by another operator using the xm command ou by another 
> binary command based on libvirt.

  yes

> If the response is yes, is it possible to introduce a global lock in Xen 
> (or in libvirt ?) to avoid conflict between  libvirt and xm command or 
> between several libvirt based commands.

  A global lock on Xen is not possible, libvirt connect to Xen only though
an RPC (well in most cases) and any other app could do the same kind of 
RPC. I don't think having a lock is possible. And even if you had a lock
a root process on domain 0 coul always do a direct hypervisor call for 
example to kill a domain. 
  In a nutshell with the current (lack of) authentication in Xen you
just can't garantee absence of conflict, and this is not a limitation
coming from libvirt.

Daniel

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